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

Engineering Commons™

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

Electrical and Computer Engineering Faculty Research & Creative Works

Discipline
Keyword
Publication Year

Articles 2641 - 2670 of 3518

Full-Text Articles in Engineering

Pulse Regulation Control Technique For Bifred Converter, Mehdi Ferdowsi, Ali Emadi, Mark Telefus, Curtis Davis Jun 2004

Pulse Regulation Control Technique For Bifred Converter, Mehdi Ferdowsi, Ali Emadi, Mark Telefus, Curtis Davis

Electrical and Computer Engineering Faculty Research & Creative Works

Pulse Regulation control scheme is presented and applied to BIFRED converter operating in discontinuous conduction mode (DCM). In contrast to the conventional control techniques, the principal idea of Pulse Regulation is to regulate the output voltage using a series of high and low power pulses generated by the current of the input inductor. In this paper, analysis of BIFRED converter operating in DCM is presented. The basic idea of Pulse Regulation as well as the estimation of the output voltage ripple is introduced. Experimental results on a prototype converter are also demonstrated.

Go to article

Image Analysis Techniques For The Automated Evaluation Of Subaxial Subluxation In Cervical Spine X-Ray Images, R. Joe Stanley, Santosh Seetharaman, L. Rodney Long, Sameer K. Antani, George R. Thoma, Edward Downey Jun 2004

Image Analysis Techniques For The Automated Evaluation Of Subaxial Subluxation In Cervical Spine X-Ray Images, R. Joe Stanley, Santosh Seetharaman, L. Rodney Long, Sameer K. Antani, George R. Thoma, Edward Downey

Electrical and Computer Engineering Faculty Research & Creative Works

Rheumatoid arthritis is a chronic inflammatory disease affecting synovial joints of the body, especially the hands and feet, spine, knees and hips. For many patients, the cervical spine is associated with rheumatoid arthritis. Subluxation is the abnormal movement of one of the bones that comprise a joint. In this research, image analysis techniques have been investigated for the recognition of cervical spine x-ray images with one or more instances of subaxial subluxation. Receiver operating characteristic curve results are presented, showing potential for subaxial subluxation discrimination on an image-by-image basis.

Go to article

Issues With Low-Input-Voltage Boost Converter Design, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman Jun 2004

Issues With Low-Input-Voltage Boost Converter Design, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

This paper addresses boost converter circuits that are built for very low input voltages, i.e. less than 1 V. Such circuits can be useful for single-cell solar and fuel cell power supplies. Important issues are physical size, high conversion ratio, efficiency, and startup. Several experimental studies show the impact of these issues. A startup technique is proposed that works for arbitrarily low input voltages.

Go to article

Testing Layered Interconnection Networks, Bin Liu, Fabrizio Lombardi, Nohpill Park, Minsu Choi Jun 2004

Testing Layered Interconnection Networks, Bin Liu, Fabrizio Lombardi, Nohpill Park, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

We present an approach for fault detection in layered interconnection networks (LINs). An LIN is a generalized multistage interconnection network commonly used in reconfigurable systems; the nets (links) are arranged in sets (referred to as layers) of different size. Switching elements (made of simple switches such as transmission-gate-like devices) are arranged in a cascade to connect pairs of layers. The switching elements of an LIN have the same number of switches, but the switching patterns may not be uniform. A comprehensive fault model for the nets and switches is assumed at physical and behavioral levels. Testing requires configuring the LIN …

Go to article

Ascertaining The Importance Of Neurons To Develop Better Brain-Machine Interfaces, Justin C. Sanchez, Jose M. Carmena, Mikhail A. Lebedev, Miguel A.L. Nicolelis, John G. Harris, Jose C. Principe Jun 2004

Ascertaining The Importance Of Neurons To Develop Better Brain-Machine Interfaces, Justin C. Sanchez, Jose M. Carmena, Mikhail A. Lebedev, Miguel A.L. Nicolelis, John G. Harris, Jose C. Principe

Electrical and Computer Engineering Faculty Research & Creative Works

In the design of brain-machine interface (BMI) algorithms, the activity of hundreds of chronically recorded neurons is used to reconstruct a variety of kinematic variables. A significant problem introduced with the use of neural ensemble inputs for model building is the explosion in the number of free parameters. Large models not only affect model generalization but also put a computational burden on computing an optimal solution especially when the goal is to implement the BMI in low-power, portable hardware. In this paper, three methods are presented to quantitatively rate the importance of neurons in neural to motor mapping, using single …

Go to article

Comparison Of Near-Field Millimeter Wave Probes For Detecting Corrosion Pit Under Paint, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, R. Zoughi, Russell A. Austin May 2004

Comparison Of Near-Field Millimeter Wave Probes For Detecting Corrosion Pit Under Paint, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, R. Zoughi, Russell A. Austin

Electrical and Computer Engineering Faculty Research & Creative Works

Corrosion pitting defection is a critical issue in the maintenance of aircraft. Near-field microwave nondestructive techniques have been successfully used for defection of corrosion under paint. In this paper a comparison between several different millimeter wave probes is made for the detection and evaluation of corrosion precursor pitting under paint at Ka-band and V-band. Since the pittings investigated here are very small in size, spatial resolution and sensitivity of the probes are critical issues. If is shown that modified open-ended rectangular probes namely, tapered waveguide and dielectric slab-loaded waveguide probes provide high resolution and sensitivity for the detection and evaluation …

Go to article

Susceptibility Characterization Of A Cavity With An Aperture By Using Slowly Rotating Em Fields: Fdtd Analysis And Measurements, Kimitoshi Murano, Takeshi Sanpei, Fengchao Xiao, Chen Wang, Yoshio Kami, James L. Drewniak May 2004

Susceptibility Characterization Of A Cavity With An Aperture By Using Slowly Rotating Em Fields: Fdtd Analysis And Measurements, Kimitoshi Murano, Takeshi Sanpei, Fengchao Xiao, Chen Wang, Yoshio Kami, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes the evaluation of the susceptibility of a cavity with an aperture using the finite-difference time-domain (FDTD) method and experimentally. To reduce the computing time, the FDTD method is used for the radiation from the cavity and the susceptibility is obtained by using the reciprocity theorem. The cavity used here is modeled after a full-tower desktop enclosure with a 3.5-in bay. The susceptibility characteristics are evaluated by measuring outputs of a monopole antenna and transmission lines installed in the cavity. The susceptibility characteristics, using a three-dimensional (3-D) map, are studied from the computed and the measured results by …

Go to article

Control Of Cascaded Multilevel Inverters, Keith Corzine, M. W. Wielebski, Fang Zheng Peng, Jin Wang May 2004

Control Of Cascaded Multilevel Inverters, Keith Corzine, M. W. Wielebski, Fang Zheng Peng, Jin Wang

Electrical and Computer Engineering Faculty Research & Creative Works

A new type of multilevel inverter is introduced which is created by cascading two three-phase three-level inverters using the load connection, but requires only one dc voltage source. This new inverter can operate as a seven-level inverter and naturally splits the power conversion into a higher-voltage lower-frequency inverter and a lower-voltage higher-frequency inverter. This type of system presents particular advantages to Naval ship propulsion systems which rely on high power quality, survivable drives. New control methods are described involving both joint and separate control of the individual three-level inverters. Simulation results demonstrate the effectiveness of both controls. A laboratory set-up …

Go to article

Determination Of The Thickness And Dielectric Constant Of A Dielectric Slab Backed By Free-Space Or A Conductor Through Inversion Of The Reflection Coefficient Of A Rectangular Waveguide Probe, Jesse Lai, Dana M. Hughes, Eric Gallaher, R. Zoughi May 2004

Determination Of The Thickness And Dielectric Constant Of A Dielectric Slab Backed By Free-Space Or A Conductor Through Inversion Of The Reflection Coefficient Of A Rectangular Waveguide Probe, Jesse Lai, Dana M. Hughes, Eric Gallaher, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Evaluation of thickness and material properties of coatings and dielectric slabs is an important practical issue. Microwave nondestructive testing techniques, using open-ended rectangular waveguide and coaxial probes have shown great potential for this purpose. However, to evaluate one parameter requires that the other be known a priori. This paper discusses the use of a relatively efficient method for evaluating both parameters simultaneously from measurements of the reflection coefficient of a test material. Results of two cases as well as a brief discussion of the limitations of the technique are provided in this paper.

Go to article

High Confidence Testing For Instrumentation System-On-Chip With Unknown-Good-Yield, N. J. Park, Bin Jin, Koshy M. George, Nohpill Park, Minsu Choi May 2004

High Confidence Testing For Instrumentation System-On-Chip With Unknown-Good-Yield, N. J. Park, Bin Jin, Koshy M. George, Nohpill Park, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

SoCs are in general built with embedded IP cores, each of which is procured from different IP providers with no prior information on known-good-yield (KGY). In practice, partial testing is a practical choice for assuring the yield of the product under the stringent time-to-market requirements. Therefore, a proper sampling technique is a key to high confidence testing and cost effectiveness. Based on previous research, this paper proposes a novel statistical testing technique for increasingly hybrid integrated systems fabricated on a single silicon die with no a-priori empirical yield data. This problem is referred to as the unknown-good-yield (UKGY) problem. The …

Go to article

Electromagnetic Interference (Emi) Of System-On-Package (Sop), Toshio Sudo, Hideki Sasaki, Norio Masuda, James L. Drewniak May 2004

Electromagnetic Interference (Emi) Of System-On-Package (Sop), Toshio Sudo, Hideki Sasaki, Norio Masuda, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic interference (EMI) issues are expected to be crucial for next-generation system-on-package (SOP) integrated high-performance digital LSIs and for radio frequency (RF) and analog circuits. Ordinarily in SOPs, high-performance digital LSIs are sources of EMI, while RF and analog circuits are affected by EMI (victims). This paper describes the following aspects of EMI in SOPs: 1) die/package-level EMI; 2) substrate-level EMI; 3) electromagnetic modeling and simulation; and 4) near electromagnetic field measurement. First, LSI designs are discussed with regard to radiated emission. The signal-return path loop and switching current in the power/ground line are inherent sources of EMI. The EMI …

Go to article

Determination Of Dielectric Property Profile In Cement-Based Materials Using Microwave Reflection And Transmission Properties, Bharath Akuthota, R. Zoughi, K. E. Kurtis May 2004

Determination Of Dielectric Property Profile In Cement-Based Materials Using Microwave Reflection And Transmission Properties, Bharath Akuthota, R. Zoughi, K. E. Kurtis

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave characterization methods are effective means for evaluating dielectric properties of materials and correlating them to their important physical, chemical and mechanical properties. For characterization purposes most materials are considered homogeneous and the measurement of their dielectric properties is fairly straightforward. However, certain materials may be considered inhomogeneous in such a way that their dielectric properties vary in a preferred direction within the material. To evaluate the dielectric property profile of these materials an electromagnetic model is necessary that can be used along with their measured reflection and transmission properties. This paper presents the development of such a model which …

Go to article

A Web-Shareable Real-World Imaging Problem For Enhancing An Image-Processing Curriculum, R. Joe Stanley, Steve Eugene Watkins, Anand Gopal, Randy Hays Moss May 2004

A Web-Shareable Real-World Imaging Problem For Enhancing An Image-Processing Curriculum, R. Joe Stanley, Steve Eugene Watkins, Anand Gopal, Randy Hays Moss

Electrical and Computer Engineering Faculty Research & Creative Works

A real-world laboratory exercise is presented for image processing and related curricula. The exercise is a traffic-monitoring problem in which a truck must be tracked as it moves across a bridge and its velocity measured. Sequential images are taken from a dedicated Web camera that views the Smart Composite Bridge on the University of Missouri-Rolla campus. The prototype bridge is a field laboratory for several interdisciplinary courses, including a Machine Vision elective. The Machine Vision image-processing elective uses the traffic-monitoring exercise to give students experience with processing complex images, tracking image markers, and applying theoretical orthographic concepts. The laboratory exercise …

Go to article

Pulse Train Control Technique For Flyback Converter, Mark Telefus, Anatoly Shteynberg, Mehdi Ferdowsi, Ali Emadi May 2004

Pulse Train Control Technique For Flyback Converter, Mark Telefus, Anatoly Shteynberg, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

Pulse TrainTM control technique is introduced and applied to flyback converter operating in discontinuous conduction mode (DCM). In contrast to the conventional pulse width modulation (PWM) control scheme, the principal idea of Pulse Train is to achieve output voltage regulation using high and low power pulses. The proposed technique is applicable to any converter operating in DCM. However, this work mainly focuses on flyback topology. In this paper, the main mathematical concept of the new control algorithm is introduced and simulations as well as experimental results are presented.

Go to article

Cost-Driven Optimization Of Fault Coverage In Combined Built-In Self-Test/Automated Test Equipment Testing, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi May 2004

Cost-Driven Optimization Of Fault Coverage In Combined Built-In Self-Test/Automated Test Equipment Testing, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

As the design and fabrication complexities for the instrumentation-on-silicon systems intensify, optimization of combined Built-In Self-Test (BIST) and Automated Test Equipment (ATE) testing becomes more desirable to meet the required fault-coverage while maintaining acceptable cost overhead. The cost associated with combined BIST/ATE testing of such systems mainly consists of the following; (1) the cost induced by the BIST area overhead and (2) the cost induced by the overall testing time. In general, BIST has faster testing speed than ATE, while it can provide only limited fault-coverage and driving higher fault-coverage from BIST means additional area cost overhead. On the other …

Go to article

Modeling Switched-Reluctance Machines By Decomposition Of Double Magnetic Saliencies, Farzad R. Salmasi, Babak Fahimi May 2004

Modeling Switched-Reluctance Machines By Decomposition Of Double Magnetic Saliencies, Farzad R. Salmasi, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel analytical model for a switched-reluctance machine (SRM) based on decomposition of its inherent double joint magnetic saliencies due to rotor and stator salient poles and saturation of magnetic field at high stator currents. with this method, the magnetic characteristics of the motor, such as flux linkage and incremental inductance, are decomposed to vector functions of rotor position and phase current. Dynamic state and torque equations for the SRM are derived on the basis of this representation. the proposed model is appropriate for online identification and for sensor less position control algorithms. It is easy to …

Go to article

An Electromagnetic Model For Evaluating Temporal Water Content Distribution And Movement In Cyclically Soaked Mortar, Shanup Peer, K. E. Kurtis, R. Zoughi Apr 2004

An Electromagnetic Model For Evaluating Temporal Water Content Distribution And Movement In Cyclically Soaked Mortar, Shanup Peer, K. E. Kurtis, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Evaluation of water distribution and its temporal movement in cement-based materials is important for assessing cement hydration, curing, and long-term performance. From a practical standpoint, it is also important to obtain this information nondestructively. Near-field microwave nondestructive evaluation methods have proven effective for evaluation of cement-based materials for their various mixture properties, including the detection of salt added to the mixing water and chloride ions entering these materials through exposure to salt water solutions. Electromagnetic modeling of the interaction of microwave signals with moist cement-based materials can provide the necessary insight to evaluate water content distribution and movement in these …

Go to article

Intelligent Control Schemes For A Static Compensator Connected To A Power Network, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Mar 2004

Intelligent Control Schemes For A Static Compensator Connected To A Power Network, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Two intelligent controllers are designed for a static compensator (STATCOM) connected to a single machine infinite bus power system (SMIB): a novel nonlinear adaptive controller using artificial neural networks based on the indirect adaptive control technique and a Takagi-Sugeno type fuzzy controller. Both schemes provide nonlinear adaptive control with better performance compared to the conventional PI controllers. Simulation results are presented to compare the performances of these controllers with that of the conventional PI controllers.

Go to article

Power Quality Enhancement Using Custom Power Devices [Book Review], Mariesa Crow Mar 2004

Power Quality Enhancement Using Custom Power Devices [Book Review], Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Go to article

Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Ali Emadi Mar 2004

Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

A new control technique for DC-DC converters is introduced and applied to a boost converter operating in discontinuous conduction mode (DCM). In contrast to conventional control methods, the principal idea of the proposed control scheme is to obtain samples of the required signals and estimate the required switch-on time. The proposed technique is applicable to any converter operating in DCM, including power factor correctors (PFC), however, this letter mainly focuses on boost topology. In this letter, the main mathematical concept of a new control algorithm is introduced, as well as the robustness investigation of the proposed method with simulation and …

Go to article

A Switched Reluctance Machine-Based Starter/Alternator For More Electric Cars, Babak Fahimi, Ali Emadi, Raymond B. Sepe Mar 2004

A Switched Reluctance Machine-Based Starter/Alternator For More Electric Cars, Babak Fahimi, Ali Emadi, Raymond B. Sepe

Electrical and Computer Engineering Faculty Research & Creative Works

Switched reluctance machines (SRMs) are considered as serious candidates for starter/alternator (S/A) systems in more electric cars. Robust performance in the presence of high temperature, safe operation, offering high efficiency, and a very long constant power region, along with a rugged structure contribute to their suitability for this high impact application. to enhance these qualities, we have developed key technologies including sensor less operation over the entire speed range and closed-loop torque and speed regulation. the present paper offers an in-depth analysis of the drive dynamics during motoring and generating modes of operation. These findings will be used to explain …

Go to article

An Efficient Multirate Simulation Technique For Power-Electronic-Based Systems, Steven D. Pekarek, Oleg Wasynczuk, Eric A. Walters, Juri V. Jatskevich, Charles E. Lucas, Ning Wu, Peter T. Lamm Feb 2004

An Efficient Multirate Simulation Technique For Power-Electronic-Based Systems, Steven D. Pekarek, Oleg Wasynczuk, Eric A. Walters, Juri V. Jatskevich, Charles E. Lucas, Ning Wu, Peter T. Lamm

Electrical and Computer Engineering Faculty Research & Creative Works

A novel multirate method of simulating power-electronic-Based systems containing a wide range of time scales is presented. in this method, any suitable integration algorithm, with fixed or variable time-step, can be applied to the fast and/or slow subsystems. the subsystems exchange coupling variables at a communication interval that can be fixed or varied dynamically depending upon the state of the system variables. the proposed multirate method is applied to two example power systems that include power-electronic subsystems. Increases in simulation speed of 183-281% over established single-rate integration algorithms are demonstrated.

Go to article

A Reconfigurable Facts System For University Laboratories, Liangying Dong, Zhiping Yang, Shen Chen, Lin Zhang, Stan Atcitty, Mariesa Crow Feb 2004

A Reconfigurable Facts System For University Laboratories, Liangying Dong, Zhiping Yang, Shen Chen, Lin Zhang, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

To fully understand the dynamic performance of the multiple flexible ac transmission systems (FACTS) devices, a hardware setup is needed to complement software simulation for university research laboratories. This paper presents the schematic and basic controls of a reconfigurable FACTS system that can be used to realize the major voltage-sourced-converter FACTS topologies: the StatCom, the static synchronous series compensator (SSSC), and the unified power-flow controller (UPFC). Furthermore, the state models and control algorithms for the FACTS devices are proposed. The digital signal processor (DSP)-based control system enables new control methods to be rapidly implemented. The comparison of the experimental and …

Go to article

Pulse Regulation Control Technique For Flyback Converter, Mehdi Ferdowsi, Ali Emadi Feb 2004

Pulse Regulation Control Technique For Flyback Converter, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

Pulse regulation, a fixed frequency control technique, is introduced and applied to flyback converter operating in discontinuous conduction mode (DCM). The control parameters are designed in a way that the converter operates as close as possible to the critical conduction mode. In contrast to the conventional pulse width modulation (PWM) control scheme, the principal idea of pulse regulation is to achieve output voltage regulation using high and low-power pulses. Pulse regulation is simple, cost effective, and enjoys a fast dynamic response. The proposed technique is applicable to any converter operating in DCM. However, this work mainly focuses on flyback topology. …

Go to article

A Multi-Processor Control System Architecture For A Cascaded Statcom With Energy Storage, Chang Qian, Stan Atcitty, Mariesa Crow Feb 2004

A Multi-Processor Control System Architecture For A Cascaded Statcom With Energy Storage, Chang Qian, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a multi-processor control system for a general purpose five-level cascaded inverter for real time power system applications. Practical design considerations for the digital controller architecture as well as the power converter are discussed and a 3 kVA laboratory prototype is presented. As a case study, a StatCom with battery energy storage was implemented on this multi-processor controlled inverter system. To eliminate the troublesome PI parameter tuning and the limitation of small signal models, which exist in conventional control for StatComs, a new and simple control method based on large signal model was designed to realize four-quadrant power …

Go to article

Common-Mode Current Due To A Trace Near A Pcb Edge And Its Suppression By A Guard Band, Yoshiki Kayano, Motoshi Tanaka, James L. Drewniak, Hiroshi Inoue Feb 2004

Common-Mode Current Due To A Trace Near A Pcb Edge And Its Suppression By A Guard Band, Yoshiki Kayano, Motoshi Tanaka, James L. Drewniak, Hiroshi Inoue

Electrical and Computer Engineering Faculty Research & Creative Works

The common-mode (CM) current due to a trace near a printed circuit board (PCB) edge, and its suppression by a guard band have been studied experimentally and with finite-difference time-domain (FDTD) modeling. As the guard band, copper tape is connected along the entire edge of the ground plane. First, a PCB electromagnetic interference (EMI) coupling path that results from the nonzero impedance of the PCB ground plane is discussed. As the trace is moved closer to the PCB edge, the CM current increases. Then, the effect of the guard band on the CM current is detailed. A guard band parallel …

Go to article

Low-Frequency Fast Inhomogeneous Plane-Wave Algorithm (Lf-Fipwa), L. (Lijun) J. Jiang, W. C. Chew Jan 2004

Low-Frequency Fast Inhomogeneous Plane-Wave Algorithm (Lf-Fipwa), L. (Lijun) J. Jiang, W. C. Chew

Electrical and Computer Engineering Faculty Research & Creative Works

A new method, the low-frequency fast inhomogeneous plane-wave algorithm (LF-FIPWA) is presented to extend the traditional multilevel fast multipole algorithm (MLFMA) and fast inhomogeneous plane-wave algorithm (FIPWA) seamlessly into the low-frequency range. It uses evanescent-wave extrapolation and translation techniques to overcome the low-frequency breakdown problem. The accuracy can be well controlled over a broad frequency range. Numerical examples show the effectiveness of this new algorithm.

Go to article

Time Series Prediction With Recurrent Neural Networks Using A Hybrid Pso-Ea Algorithm, Nian Zhang, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Xindi Cai Jan 2004

Time Series Prediction With Recurrent Neural Networks Using A Hybrid Pso-Ea Algorithm, Nian Zhang, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Xindi Cai

Electrical and Computer Engineering Faculty Research & Creative Works

To predict the 100 missing values from the time series consisting of 5000 data given for the IJCNN 2004 time series prediction competition, we applied an architecture which automates the design of recurrent neural networks using a new evolutionary learning algorithm. This new evolutionary learning algorithm is based on a hybrid of particle swarm optimization (PSO) and evolutionary algorithm (EA). By combining the searching abilities of these two global optimization methods, the evolution of individuals is no longer restricted to be in the same generation, and better performed individuals may produce offspring to replace those with poor performance. The novel …

Go to article

Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng Jan 2004

Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

New results are presented for the ergodic capacity of spatially-correlated, time-varying and frequency-selective (i.e., triply selective) MIMO Rayleigh fading channels. Simplified capacity formulas are also derived for special cases such as SIMO and MISO triply selective fading channels. A closed form formula is proposed that quantifies the effect of the frequency-selective fading on the ergodic capacity into an intersymbol interference (ISI) degradation factor. It is discovered that, in general frequency-selective MIMO channels, the ISI inter-tap correlations reduce the ergodic capacity compared to the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap …

Go to article

Electromagnetic Analysis For Vehicle Antenna Development Using Method Of Auxiliary Sources, David Pommerenke, Kai Xiao, R. S. Zaridze, D. G. Kakulia, K. N. Tavzarashvili, G. N. Ghvedashvili Jan 2004

Electromagnetic Analysis For Vehicle Antenna Development Using Method Of Auxiliary Sources, David Pommerenke, Kai Xiao, R. S. Zaridze, D. G. Kakulia, K. N. Tavzarashvili, G. N. Ghvedashvili

Electrical and Computer Engineering Faculty Research & Creative Works

In paper [l] the electromagnetic analysis of large semi-open structures like vehicles was presented formulated as scattering problem, illuminated by a wide range of incident EM fields. The effect of resonances within the semi-open structure on the RCS, near fields and pattem of reradiated fields had been shown. In this paper the interaction of the entire semi-open structure on the performance of an antenna is considered together with the investigation of near field distributions inside the cavity. The Method of Auxiliary Sources (MAS) [2] is utilized. For a simple geometry the results are compared to measurements.

Go to article

First Prev Next Last