Open Access. Powered by Scholars. Published by Universities.®

Electrical and Computer Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

2011

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1 - 30 of 1293

Full-Text Articles in Electrical and Computer Engineering

Internal Electric Fields Due To Piezoelectric And Spontaneous Polarizations In Cdzno/Mgzno Quantum Well, H. C. Jeon, S. J. Lee, Tae Won Kang, S. H. Park, Yung Kee Yeo, T. F. George Dec 2011

Internal Electric Fields Due To Piezoelectric And Spontaneous Polarizations In Cdzno/Mgzno Quantum Well, H. C. Jeon, S. J. Lee, Tae Won Kang, S. H. Park, Yung Kee Yeo, T. F. George

Faculty Publications

We have investigated optical properties as a function of internal and external fields in the quantum well (QW). Optical properties of CdZnO/MgZnO QW structures are investigated by using many‐body effects. The CdZnO/MgZnO QW structure with high Cd composition is found to have smaller optical gain because the strain‐induced piezoelectric polarization and the spontaneous polarization in the well increase with the inclusion of Cd. These results demonstrate that high performance laser diode operation can be realized in CdZnO/MgZnO QW structures by reducing those polarizations adopting dipole reverse method.


Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb Dec 2011

Exploitation Of Unintentional Information Leakage From Integrated Circuits, William E. Cobb

Theses and Dissertations

Unintentional electromagnetic emissions are used to recognize or verify the identity of a unique integrated circuit (IC) based on fabrication process-induced variations in a manner analogous to biometric human identification. The effectiveness of the technique is demonstrated through an extensive empirical study, with results presented indicating correct device identification success rates of greater than 99:5%, and average verification equal error rates (EERs) of less than 0:05% for 40 near-identical devices. The proposed approach is suitable for security applications involving commodity commercial ICs, with substantial cost and scalability advantages over existing approaches. A systematic leakage mapping methodology is also proposed to …


Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp Dec 2011

Linear-Quadratic Control Of A Mems Micromirror Using Kalman Filtering, Jamie P. Schnapp

Theses and Dissertations

The deflection limitations of electrostatic flexure-beam actuators are well known. Specifically, as the beam is actuated and the gap traversed, the restoring force necessary for equilibrium increases proportionally with the displacement to first order, while the electrostatic actuating force increases with the inverse square of the gap. Equilibrium, and thus stable open-loop voltage control, ceases at one-third the total gap distance, leading to actuator snap-in. A Kalman Filter is designed with an appropriately complex state dynamics model to accurately estimate actuator deflection given voltage input and capacitance measurements, which are then used by a Linear Quadratic controller to generate a …


Highly Sensitive Refractive Index Optical Fiber Sensors Fabricated By A Femtosecond Laser, Jinpeng Yang, Lan Jiang, Sumei Wang, Qianghua Chen, Benye Li, Hai Xiao Dec 2011

Highly Sensitive Refractive Index Optical Fiber Sensors Fabricated By A Femtosecond Laser, Jinpeng Yang, Lan Jiang, Sumei Wang, Qianghua Chen, Benye Li, Hai Xiao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Highly sensitive and robust refractive index (RI) fiber sensors are proposed, which are based on concatenating two micro air-cavities. the micro air-cavities embedded in the fiber along the core axis are fabricated by combining the techniques of femtosecond laser micromachining and arc fusion splicing. the full width at half-maximum (FWHM) of an attenuation peak of a sensor in air is 0.048 nm, and the extinction ratio is ∼15 dB. When the diameter of the cavity is slightly larger than the fiber core diameter, the sensor is highly sensitive to external RI changes. a high sensitivity of 172.4 nm/refractive index unit …


Uwb System Based On Energy Detection Of Derivatives Of The Gaussian Pulse, Song Cui, Fuqin Xiong Dec 2011

Uwb System Based On Energy Detection Of Derivatives Of The Gaussian Pulse, Song Cui, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

A new method for energy detection ultra-wideband systems is proposed. The transmitter of this method uses two pulses that are different-order derivatives of the Gaussian pulse to transmit bit 0 or 1. These pulses are appropriately chosen to separate their spectra in the frequency domain. The receiver is composed of two energydetection branches. Each branch has a filter which captures the signal energy of either bit 0 or 1. The outputs of the two branches are subtracted from each other to generate the decision statistic. The value of this decision statistic is compared to the threshold to determine the transmitted …


Adaptive Mitigation In The Electric Power Sector, Lesley K. Mcallister Dec 2011

Adaptive Mitigation In The Electric Power Sector, Lesley K. Mcallister

BYU Law Review

No abstract provided.


Computational Modeling For Transportation Network Security, Sherif A. Tolba Dec 2011

Computational Modeling For Transportation Network Security, Sherif A. Tolba

Master's Theses

No abstract provided.


Dynamic Test Scheduling In Hardware-In-The-Loop Simulation Of Commercial Vehicles, Tenil Cletus Dec 2011

Dynamic Test Scheduling In Hardware-In-The-Loop Simulation Of Commercial Vehicles, Tenil Cletus

Master's Theses

Modern day commercial vehicles are controlled by various Electronic Control Units (ECU). They are not only tested as single units, but also by networking them in Controlled Area Network bus (CAN) to form a complete electrical control system. This is achieved using Hardware In the Loop (HIL) Integration Lab. In HIL, the electrical system is connected to a real time mathematical model of the vehicle plus it’s environment so as to form a loop.

Testing functionality of the electrical system begins by defining functional tests. An example would be testing cruise control activation. Executing each test is made possible by …


Identification Of Power System Stability Using Relevant Modes, Rogers Whitlock Jr Dec 2011

Identification Of Power System Stability Using Relevant Modes, Rogers Whitlock Jr

LSU New Orleans Theses and Dissertations

The purpose of this investigation is to identify appropriate location of capacitor banks and sources of reactive power by studying power system stability in the vicinity of system equilibrium states. The locations for reactive power sources are determined by identifying those modes of the system that participate most in the system behavior in general and in dictating the final state of the system after experiencing faults or disturbances. To identify the relevant modes of the system that participate most in the system dynamic, we shall make use of modal and participation analysis for different system conditions. We also apply modal …


Should Distribution Systems Engineering Be Taught At The Undergraduate Level?, Badrul Chowdhury, Anil Pahwa Dec 2011

Should Distribution Systems Engineering Be Taught At The Undergraduate Level?, Badrul Chowdhury, Anil Pahwa

Electrical and Computer Engineering Faculty Research & Creative Works

Although there are some exceptions, a distribution systems course is not part of a typical undergraduate curriculum. the course is usually taught at the graduate level. Teaching a distribution systems course requires the student to have a background in balanced three-phase power system modeling such as that obtained from a first power systems analysis course. the requirement to add breadth to an undergraduate curriculum often precludes the notion of depth in any one area unless a student takes the depth courses as technical or free electives. an argument could be made that a distribution systems course does not contain much …


On-Line Voltage Stability Load Index Estimation Based On Pmu Measurements, K. Joseph Makasa, Ganesh K. Venayagamoorthy Dec 2011

On-Line Voltage Stability Load Index Estimation Based On Pmu Measurements, K. Joseph Makasa, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

A new method for estimation of Voltage Stability Load Index (VSLI) for a power system using data from optimally located phasor measurement units (PMU) is presented in this paper. Optimal PMU placement was carried out considering islanding operating conditions. vs.LI is estimated using a kind of recurrent neural network known as the Echo State Network (ESN). the development ESN is computational efficient and provides accurate estimation. Results of optimal PMU placement for normal and islanded operating conditions, and ESN estimation of vs.LI on the IEEE 14 bus system is presented. © 2011 IEEE.


Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley Dec 2011

Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper summarizes past and ongoing research in the area of the application of computational intelligence (CI) for control of wind turbine generators (WTGs). Several intelligent design approaches and control strategies, including optimal design of WTG controllers using particle swarm optimization (PSO) and mean-variance optimization (MVO) algorithms and adaptive critic design-Based coordinated optimal adaptive control for wind plants and shunt FACTS devices, are presented for dynamic performance and fault ride-through enhancement of WTGs and the associated power grid. the effectiveness of these intelligent design approaches and control strategies are demonstrated by nonreal- and real-time simulations in PSCAD/EMTDC and RSCAD/RTDS, respectively. …


Risk Assessment Of Cascading Outages: Part I - Overview Of Methodologies, Marianna Vaiman, Keith Bell, Yousu Chen, Badrul H. Chowdhury, Ian Dobson, Paul Hines, Milorad Papic, Stephen S. Miller, Pei Zhang Dec 2011

Risk Assessment Of Cascading Outages: Part I - Overview Of Methodologies, Marianna Vaiman, Keith Bell, Yousu Chen, Badrul H. Chowdhury, Ian Dobson, Paul Hines, Milorad Papic, Stephen S. Miller, Pei Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper is a result of ongoing activity carried out by Understanding, Prediction, Mitigation and Restoration of Cascading Failures Task Force under IEEE Computer Analytical Methods Subcommittee (CAMS). the task force's previous papers are focused on general aspects of cascading outages such as understanding, prediction, prevention and restoration from cascading failures. This is the first of two new papers, which extend this previous work to summarize the state of the art in cascading failure risk analysis methodologies and modeling tools. This paper is intended to be a reference document to summarize the state of the art in the methodologies for …


Intelligent Methods For Smart Microgrids, Joydeep Mitra, Niannian Cai, Mo Yuen Chow, Sukumar Kamalasadan, Wenxin Liu, Wei Qiao, Sri Niwas Singh, Anurag K. Srivastava, Sanjeev K. Srivastava, Ganesh K. Venayagamoorthy, Ziang Zhang Dec 2011

Intelligent Methods For Smart Microgrids, Joydeep Mitra, Niannian Cai, Mo Yuen Chow, Sukumar Kamalasadan, Wenxin Liu, Wei Qiao, Sri Niwas Singh, Anurag K. Srivastava, Sanjeev K. Srivastava, Ganesh K. Venayagamoorthy, Ziang Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper summarizes ongoing research in the application of intelligent methods to the design, modeling, simulation and control of microgrids including optimal design of microgrids, and centralized and decentralized control. © 2011 IEEE.


Innovative Smart Grid Control Technologies, Ganesh K. Venayagamoorthy Dec 2011

Innovative Smart Grid Control Technologies, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The smart electric power grid will evolve into a very complex adaptive system under semi-autonomous distributed control. It will be spatially and temporally complex, non-convex, non-linear and non-stationary, with lots of variability and uncertainties beyond what the traditional power system experiences today. the distributed integration of intermittent sources of energy and energy storage to a power grid further adds complexity and challenges to modeling, control and optimization of the grid. Innovative control technologies are needed to handle the growing complexity of a smart grid, maximize the penetration of renewable energy, and provide maximum utilization of available energy storage, especially plug-in …


Intelligent Sense-Making For Smart Grid Stability, Ganesh K. Venayagamoorthy Dec 2011

Intelligent Sense-Making For Smart Grid Stability, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power systems of the future - smart grids - will see an increase in both renewable energy sources and load demand, thus increasing the need for fast dynamic reconfiguration of system parameters to handle energy and load dispatches. Power systems will need to be monitored continuously to maintain stability under normal and abnormal operating conditions and when facing disturbances. a combination of system state prediction, dynamic power flow, system optimization, and solution stability checking will allow for a more reliable, affordable, efficient and clean power grid. the optimization and control systems on a smart grid will require a computational …


Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner Dec 2011

Development Of A Grond-Based High-Resolution 3d-Sar System For Studying The Microwave Scattering Characteristics Of Trees, Justin Frank Penner

Theses and Dissertations

This thesis presents the development of a high-resolution ground-based 3D-SAR system and investigates its application to microwave-vegetation studies. The development process of the system is detailed including an enumeration of high-level requirements, discussions on key design issues, and detailed descriptions of the system down to a component level. The system operates on a 5.4 GHz (C-band) signal, provides a synthetic aperture area of 1.7 m x 1.7 m, and offers resolution of 0.75 m x 0.3 m x 0.3 m (range x azimuth x elevation). The system is employed on several trees with varying physical characteristics. The resulting imagery demonstrates …


Navigation And Position Determination With A Multicarrier Modulation Signal Of Opportunity, Richard K. Martin, Jamie S. Velotta, John F. Raquet Dec 2011

Navigation And Position Determination With A Multicarrier Modulation Signal Of Opportunity, Richard K. Martin, Jamie S. Velotta, John F. Raquet

AFIT Patents

A multicarrier modulation position determination method that includes deploying at least one known receiver with a known location and a second receiver with an unknown location. At least two signals of opportunity with different locations are obtained by both the receiver and the second receiver. The signals having a plurality of block data, the block data having block boundaries. The block boundaries including a beginning block boundary and an end block boundary. The block data further including a cyclic prefix at the beginning block boundary. Acquiring a plurality of data samples for at least a portion of the block data …


Flexible Multitouch Electroluminescent Display, Michael E. Miller, John W. Harmer Dec 2011

Flexible Multitouch Electroluminescent Display, Michael E. Miller, John W. Harmer

AFIT Patents

A display device including a touch sensitive EL display having a flexible substrate; one or more power busses and one or more EL elements disposed over the flexible substrate; and a plurality of distributed chiplets arranged so that at least two chiplets are associated with each of a plurality of touch sensitive areas on the EL display and for sensing stress or strain associated with bending of the flexible substrate or the chiplet substrate to provide respective displacement signals corresponding to the touch sensitive areas; each chiplet connected to one or more of the power busses and one or more …


Lithium-Based Battery System Management And Balancing, William Joel Schmidt Iii Dec 2011

Lithium-Based Battery System Management And Balancing, William Joel Schmidt Iii

Purdue Polytechnic Masters Theses

This thesis builds upon previous work completed for the design and evaluation of active lithium battery system management. Simulations were performed to provide a comparison for the hardware that was designed, built, and tested. An analysis of the simulation and hardware results was completed to support or disprove the initial hypothesis. A DC-DC converter was used as the source for the balancing current. Lithium polymer batteries with a 5Ah capacity were used for testing the designed hardware. The findings showed that there is a reduction in the system voltage swing during balancing as well as less time taken to decrease …


Trustworthy Coordination For Web Services Atomic Transactions, Honglei Zhang, Hua Chai, Wenbing Zhao, P.M. Melliar-Smith, L.E. Moser Dec 2011

Trustworthy Coordination For Web Services Atomic Transactions, Honglei Zhang, Hua Chai, Wenbing Zhao, P.M. Melliar-Smith, L.E. Moser

Electrical and Computer Engineering Faculty Publications

The Web Services Atomic Transactions (WS-AT) specification makes it possible for businesses to engage in standard distributed transaction processing over the Internet using Web Services technology. For such business applications, trustworthy coordination of WS-AT is crucial. In this paper, we explain how to render WS-AT coordination trustworthy by applying Byzantine Fault Tolerance (BFT) techniques. More specifically, we show how to protect the core services described in the WS-AT specification, namely, the Activation service, the Registration service, the Completion service and the Coordinator service, against Byzantine faults. The main contribution of this work is that it exploits the semantics of the …


Integration Of Upqc For Power Quality Improvement In Distributed Generation Network – A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon Dec 2011

Integration Of Upqc For Power Quality Improvement In Distributed Generation Network – A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Conference Papers

In this paper a technical review of the integration of a Unified Power Quality Conditioner (UPQC) in a distributed generation network is presented. Although the primary task of UPQC is to minimize grid voltage and load current disturbances along with reactive and harmonic power compensation, additional functionalities such as compensation of voltage interruption and active power transfer to the load and grid have also been identified. Connection methodologies with their advantages and disadvantages are also described. Recent improvements in capacity expansion techniques and future trends for the application of UPQC in distributed modes are also identified.


Ann Based Load Identification And Forecasting System For The Built Environment, Hosen Hasna Dec 2011

Ann Based Load Identification And Forecasting System For The Built Environment, Hosen Hasna

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

"Phantom Loads" cause energy waste in homes and the built environment as a whole. Consumers spend more than $3 billion a year on "Phantom Load" in the United States alone. The goal of this work is to conserve energy by increasing consumer awareness on their energy usage and appropriate tools which in turn will be reducing and /or eliminating phantom loads and mismanagement of the load in the built environment. A further goal is to improve upon existing power distribution systems in the built environment with limited hardware additions to increase energy conservation. This work investigates remote identification of load …


An Rf Cmos Implementation Of An Adaptive Filter For Narrow-Band Interferer Suppression In Uwb Systems, Markus Both Dec 2011

An Rf Cmos Implementation Of An Adaptive Filter For Narrow-Band Interferer Suppression In Uwb Systems, Markus Both

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

Ultra-wideband (UWB) technology is a new type of technology for wireless communication that is based on the transmission of low power sub-nanosecond pulses. UWB communication utilizes a large bandwidth that overlaps and is coexistent with other wireless communication standards that can be also considered as narrow-band interferers. Because UWB systems are highly susceptible to narrow-band interferers, there is a demand for interferer suppression. An adaptive filter consisting of a two-element diversity receiver that performs minimum mean square error combining (MMSE) by the LMS algorithm is proposed. Thereby the elements of the LMS algorithm as well as the receiver LNA were …


Highly Efficient Maximum Power Point Tracking Using A Quasi-Double-Boost Dc/Dc Converter For Photovoltaic Systems, Christopher J. Lohmeier Dec 2011

Highly Efficient Maximum Power Point Tracking Using A Quasi-Double-Boost Dc/Dc Converter For Photovoltaic Systems, Christopher J. Lohmeier

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

Solar photovoltaic (PV) panels are a great source of renewable energy generation. The biggest problem with solar systems is relatively low efficiency and high cost. This work hopes to alleviate this problem by using novel power electronic converter and control designs. An electronic DC/DC converter, called “Quasi-Double-Boost DC/DC Converter,” is designed for a Solar PV system. A Maximum Power Point Tracking (MTTP) algorithm is implemented through this converter. This algorithm allows the PV system to work at its highest efficiency. Different current sensing and sensorless technologies used with the converter for the MPPT algorithm are offered and tested. Design aspects …


The Extended Preferred Ordering Theorem For Radar Tracking Using The Extended Kalman Filter, Donald Leskiw Dec 2011

The Extended Preferred Ordering Theorem For Radar Tracking Using The Extended Kalman Filter, Donald Leskiw

Electrical Engineering and Computer Science - Dissertations

A certain problem in nonlinear estimation exists in radar tracking. Usually radar detections provide instantaneous position measurements in radar (polar) coordinates at discrete times, while tracks (estimated positions and motions over continuous time) are determined in rectangular coordinates; and the linear Kalman filter (LKF) is used as the estimator. Less common, the LKF is used to determine the tracks in radar coordinates, which are then converted into rectangular coordinates. Rarely is the extended Kalman filter (EKF) used, where the tracks are directly determined in rectangular coordinates from the radar detections via a local linearization. And so most radar tracks tend …


Wavelength Dependence Of Transverse Mode Coupling With/Without E-Block Of Gan Laser Cavity, K. Lal, G. Chavoor, Xiaomin Jin Dec 2011

Wavelength Dependence Of Transverse Mode Coupling With/Without E-Block Of Gan Laser Cavity, K. Lal, G. Chavoor, Xiaomin Jin

Electrical Engineering

Transverse mode wavelength dependence in the gallium nitride (GaN) laser cavity is a new topic. Modal analysis simulations are run to optimize the blue GaN-based laser diode with a wavelength of 400, 430, and 460 nm. It is shown that the optical confinement factor (OCF) has a strong dependence on wavelength of emission and electron-block (e-block) thickness. The OCF can be changed from 4.9% at a 460-nm wavelength to 7.6% at 400 nm, which is a 55% difference. The effect of adding an e-block layer of different widths is also investigated with results showing that an e-block layer can change …


Mapping Device With Wireless Communication, Xiangyu Liu Dec 2011

Mapping Device With Wireless Communication, Xiangyu Liu

Electrical Engineering Undergraduate Honors Theses

Wireless communication is one of the most powerful communication methods that people use nowadays. The key advantage of wireless communications is that it can cover large distances without having to run any cables from one end to the other. Based on this advantage, wireless communication has many important applications, such as remote controls, cell phones, and global positioning system (GPS). This senior design project is developed to use wireless communication technology to map the geographic characteristics of an unknown place. It contains two wireless communication modules with Atmega1281 microprocessor, two robots with the 8051 microcontroller, six pairs of infrared transmitters …


Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez Dec 2011

Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez

Electrical and Computer Engineering Faculty Publications

Fast nonuniform interpolation based super-resolution (SR) has traditionally been limited to applications with translational interframe motion. This is in part because such methods are based on an underlying assumption that the warping and blurring components in the observation model commute. For translational motion this is the case, but it is not true in general. This presents a problem for applications such as airborne imaging where translation may be insufficient. Here we present a new Fourier domain analysis to show that, for many image systems, an affine warping model with limited zoom and shear approximately commutes with the point spread function …


Light Coupling Between A Singlemode-Multimode-Singlemode (Sms) Fiber Structure And A Long Period Fiber Gating, Qiang Wu, Yuliya Semenova, Youqiao Ma, Pengfei Wang, Tuan Gao, Long Jin, Gerald Farrell Dec 2011