Electrical and Computer Engineering Commons^™

Computer-Aided Testing Of Electrical Machines: Software Development, Max Darwin Anderson, Steven A. Hauk, Robert Laramore, Hardy J. Pottinger

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Stability Of Polynomials Under Correlated Coefficient Perturbations., M. K. Saridereli, Frank J. Kern

Electrical and Computer Engineering Faculty Research & Creative Works

The robust stability of polynomials with respect to real parameter variations is investigated. The coefficients of the polynomial are assumed to be linear functions of several real parameters. An algorithm to calculate the maximum allowable variations of the parameters so the roots still remain in prescribed regions of the complex plane is presented. Examples are given to illustrate the method.

Robust Control Of A Csi-Fed Induction Motor Drive System, Rajiva Prakash, Vittal S. Rao, Frank J. Kern

Electrical and Computer Engineering Faculty Research & Creative Works

An application of modern control theory to the control of a current-source-inverter (CSI) fed induction motor drive system is presented. A linear quadratic Gaussian (LQG) control scheme is developed in which the Kaiman filter is tuned for high robustness by a method of Doyle and Stein. The design is carried out for a sample system, and the robustness analysis and computer simulation results are included. Copyright © 1987 by The Institute of Electrical and Electronics Engineers, Inc.

Computer-Aided Testing Of Electrical Machines: Software Development, Max Darwin Anderson, Steven A. Hauk, Robert Laramore, Hardy J. Pottinger

Electrical and Computer Engineering Faculty Research & Creative Works

Computer-aided test stations have been developed for research, experimentation, and testing of electric motors and generators. Data acquisition and control of the machines and drives are provided through a computer and its interfaces. Machines are connected to the computer through transducers for data acquisition, and power electronic drives for machine control. General software was written to enable the monitoring of all transducers continuously on the CRT screen while giving the user manual control of the machines and drives. Specialized software was written for automatic control of the induction, dc, and synchronous machines for specific experiments on each type of machine. …

A Limitation To The Use Of A Constructive Approach In The Stability Analysis Of Fixed-Point Digital Controllers, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

A limitation to the application of a constructive algorithm to the stability analysis of fixed-point digital controllers is demonstrated by an example. The particular system analyzed consists of a fixed-point PI digital controller regulating a first-order process.

Estimation Approach To Locating Buried Geological Interfaces, A. Omar, A. Addeeb, C. Slivinsky, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

The objective of the estimation work described in this paper is to improve algorithms for reconstructing the geometric configuration of acoustic reflecting surfaces. The conventional migration method of locating these surfaces is reviewed. A recent imaging condition which is closely related to the boundary condition at the geological interface is then described. This later procedure results in two outputs. One can be used to reconstruct the shape of the unknown acoustic reflector, while the second output estimates the acoustic wavespeed on the transmission side of the boundary. When noise is present in the reflected signal, the performance of the method …

Maximum-Likelihood Estimation Of Time-Varying Delay-Part I, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Presents, for the First Time, the Exact Theoretical Solution to the Problem of Maximum-Likelihood (ML) Estimation of Time-Varying Delay d(t) between a Random Signal s(t) Received at One Point in the Presence of Uncorrelated Noise, and the Time-Delayed, Scaled Version as(t - d(t)) of that Signal Received at Another Point in the Presence of Uncorrelated Noise. the Signal is Modeled as a Sample Function of a Nonstationary Gaussian Random Process and the Observation Interval is Arbitrary. the Analysis of This Paper Represents a Generalization of that of Knapp and Carter [1], Who Derived the ML Estimator for the …

A New Approach To Signal Registration With The Emphasis On Variable Time Delay Estimation, Mohamad Namazi, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

Signal Registration is Concerned with the Problem of Estimating a Varying Displacement between Two Random Processes. We Approach Signal Registration Here as a Recursive Demodulation Problem in Which the Recursion is between Signal Estimations and Displacement Estimation. Special Attention is Given to the Problem of Estimating a Variable Time Delay. Thus, We Present New Algorithms for Estimating D(T) from Received Processes:

r₁(t) = s(t) + n₁(t)

R₂(t) = s(t - D(t)) +n₂(t)

Where s [Formula Omitted] is Signal and n₁ (•) and n₂ (•) Are Noise. Simulation Results Are Presented …

A Log-Spiral, Radiating-Line Antenna, James L. Drewniak, P. E. Mayes, D. Tanner, R. Waller

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Growth Of Ultrafine Particles By Brownian Coagulation, S. H. Suck Salk, R. E. Thurman, Chang-Soo Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Current atmospheric observations tend to support the view that continental tropospheric aerosols (particularly urban aerosols) show multimodal mass distributions in the size range of 0.01-100 μm. The origin of these aerosols is both natural and anthropogenic. Recently, trimodal sub-μm size distributions from combustion measurements at 0.008, 0.035 and 0.15 μm were also observed. Our interest in the present study is the secondary process of growth of sub-μm size aerosols by the coagulation process alone. Using the 'J-space' (integer-space) distribution method of Salk (Suck) and Brock (1979, J. Aerosol Sci. 10, 58-590), we report an accurate numerical simulation study of the …

Electrodeposition And Analysis Of Tin Selenide Films, R. D. Engelken, Jack L. Boone, A. Shahnazary

Electrical and Computer Engineering Faculty Research & Creative Works

Sn1±xSe films have been electrodeposited from aqueous solutions containing SnCl2 and ionically dissolved SeO2 or H2SeO3 and DMF solutions containing SnCl2 and molecularly dissolved selenium powder. The as-deposited films ranged from amorphous to polycrystalline and exhibited indirect or nondirect bandgaps from 0.85 to 0.95 eV. There was little difference between the appearance or material data of the films grown by the two techniques. Direct reaction between Sn++ and H2SeO3 or HSeO3_ in the aqueous solutions yielded a Se/SnxSe suspension/precipitate. Although this does not seem to have any serious effect on the deposition process, it does produce a decrease in the …

An Interactive Power System Analyzer With Graphics Display For Educational Use, C. H. Lo, Max Darwin Anderson, Earl F. Richards

Electrical and Computer Engineering Faculty Research & Creative Works

The paper presents a student-oriented power-system analyzer with an interactive graphics display. Its capabilities include studies of (1) load flow, (2) load and generation, (3) voltage level control, (4) economic dispatch, and (5) contingency and planning analysis. Power network configurations of up to 30 buses can be presented clearly on one screen. The interactive nature of this program makes such studies effective and easy to use. With the support of a computer with graphics software and many graphics terminals, this program can be a useful teaching tool for power system studies. Copyright © 1986 by The Institute of Electrical and …

Alternate Presentation Of Fourier Transform Development From Fourier Series., Gordon E. Carlson

Electrical and Computer Engineering Faculty Research & Creative Works

An alternate presentation of the development of the Fourier transform from the complex exponential Fourier series is presented. It uses spectral concepts to aid the mathematical development and a redefined spectral form for the spectral information obtained with the Fourier series. It has been used a number of times in the classroom and has been found to aid the students' understanding of the Fourier transform and the spectra of an aperiodic signal.

An Interactive Power System Analyzer With Graphics For Educational Use, Chin Hwanglo, Max Darwin Anderson, Earl F. Richards

Electrical and Computer Engineering Faculty Research & Creative Works

The paper presents a student-oriented power system analyzer with an interactive graphics display. Its capabilities include studies of (1) load flow, (2) load and generation, (3) voltage level control, (4) economic dispatch, and (5) contingency and planning analysis. Power network configurations of up to 30 buses can be presented clearly on one screen. The interactive nature of this program makes such studies effective and easy to use. With the support of a computer with graphics software and many graphics terminals, this program can be a useful teaching tool for power system studies. Copyright © 1986 by The Institute of Electrical …

Free Electron Density Measurements By Ir Absorption In Cds, Jack L. Boone, Gene Cantwell, Michael D. Shaw

Electrical and Computer Engineering Faculty Research & Creative Works

A contactless method for determining the spatial variation of the free carrier density in CdS is presented. The method involves the correlation of IR transmission with the free carrier density via the IR absorption coefficient. Preliminary measurements indicate a free electron density sensitivity of less than 5x1014 cm-3 and a spatial resolution which is limited only by the spot size of a CO2 (λ=10.6 μm) laser; this should be of the order of 100 μm. Experimental results indicate that the predominate scattering is due to impurity interaction at room temperature; this is indicative of the high degree of compensation in …

Minimum Probability Of Electron-Hole Pair Generation By Blackbody Radiation, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

Using the small-perturbation assumption that all the useful work is in the form of electron-hole pairs when photons from a blackbody radiation source are incident on a quantum device, we derive the minimum probability of generation of one or more pairs of electron holes. Using the Planck radiation formula for the solar spectrum at 6000 K and for the quantum device at 300 K, this minimum probability is about 0.8 at low photon frequency and approaches the limiting value of 0.95 at high frequency. Its relation to maximum efficiency of a quantum device is discussed.

Stability Analysis Of Fixed-Point Digital Filters Using Computer Generated Lyapunov Functions- Part I: Direct Form And Coupled Form Filters, A. Michel, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

We demonstrate the applicability of the constructive stability algorithm of Brayton and Tong in the stability analysis of fixed-point digital filters. In the present paper, we consider direct form and coupled form filters while in a companion paper we treat wave digital filters and lattice filters. We compare our results with existing ones which deal with either the global asymptotic stability of digital filters or with existence (resp., nonexistence) of limit cycles in digital filters. Several of the present results are new while some of the present results constitute improvements over existing results. In a few cases, the present results …

Stability Analysis Of Fixed-Point Digital Filters Using Computer Generated Lyapunov Functions- Part Ii: Wave Digital Filters And Lattice Digital Filters, A. Michel, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

In a companion paper [4], we utilize the constructive stability algorithm of Brayton and Tong in the stability analysis of fixed-point digital filters which are in the direct form and in the coupled form. We continue this work in the present paper by considering wave digital filters and lattice digital filters. We believe that the results of the present paper and its companion paper demonstrate that the constructive algorithm constitutes an effective and general approach in the qualitative analysis of fixed-pointed digital filters.

Growth Of Tungsten Selenide Films Through Pyrolytic Conversion And Anodic Electrooxidation Of Ammonium Selenotungstate ((Nh4)2wse4), R. D. Engelken, T. (Thomas) P. Van Doren, Jack L. Boone, A. K. Berry, A. Shahnazary

Electrical and Computer Engineering Faculty Research & Creative Works

WxSey thin films have been prepared by the spray pyrolysis and anodic electrodeposition of solutions of ammonium selenotungstate, (NH4)2WSe4, with y/x usually between two and three for the sprayed films and y x>>1 for the electrodeposited films. The sprayed films indicated regions of crystalline WSe2 and have optical absorbance spectra consistent with a mixture of WSe2, WSe3, and selenium. The electrodeposited films are totally amorphous, highly photoconductive, and have optical absorbance spectra typical of amorphous or vitreous selenium. The sprayed films transform into WO3 at temperatures greater than 350°C in the presence of oxygen wile the electrode-posited films tend …

Fourier Transforms Over Warped Domains., Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

The Author Shows that There May Be an Advantage to Computing Fourier Transforms Over Warped Domains. an Example of Such an Improvement is Provided. It is Also Shown How the Fourier Transform May Be Evaluated from Data Observed over a Warped Domain.

Laser-Induced Surface Diffusion, Cheng-Hsiao Wu, Jonathan I. Gittleman

Electrical and Computer Engineering Faculty Research & Creative Works

A Brownian motion model for laser-induced surface diffusion is proposed to account for the kinetics of surface transport of the evaporated molecules from a thin discontinuous film under a focused laser beam. The model is solved exactly where the evaporation rate of the molecules is assumed to be proportional to the temperature rise above the ambient of the absorber layer. The surface diffusion constant and molecular velocity are obtained by comparing the results of calculations with transmission electron micrographs of recorded pits in Te trilayer opticial discs. These values are in good agreement with Einstein's relation.

On The Relation Between Triangular Matrix Decomposition And Linear Interpolation, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

The December 1983 Letter by C. W. Therrien Concerning the Relation between Triangular Matrix Decomposition and Linear Prediction is Extended to Include Linear Interpolation. © 1984 IEEE

A Microprocessor-Controlled Message Display System, Paul D. Stigall, Brian E. Lenharth

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Experimental Investigation Of The Field And Stray Losses Of The End Bells Of An Induction Motor, Hu Ming-Zheng, George Mcpherson

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Statistical Analysis Of Breakdown In Transformer Oil., J. Derald Morgan, M. A. Abdellah, Frank Ferracane

Electrical and Computer Engineering Faculty Research & Creative Works

The statistics of breakdown for transformer oil in a uniform field gap is an important design consideration. The theoretical probability distribution which closely fits the experimental data under 60 Hz ac voltage, positive and negative lightning impulses and positive and negative switching surges is evaluated and a statistical distribution is suggested.

Distribution System Protection With Decentralized Generation Introduced Into The System, Behruz Fardanesh, Earl F. Richards

Electrical and Computer Engineering Faculty Research & Creative Works

Cogeneration from renewable energy sources has been universally proposed as a partial alternative to the solution of our nation's energy problems. New technical, safety, and operational problems are introduced when this generation is placed into a distribution grid. Addressed is the problem of distribution system protection with the introduction of cogeneration sources and the changes and modifications which may be required in the application of present-day protection devices. A sample system is considered, and system protection and coordination with and without cogeneration has been calculated through a digital fault and system protection coordination program. The results indicate through the study …

Correction To “Two-Dimensional Markov Representations Of Sampled Images”, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Limiting Efficiencies For Multiple Energy-Gap Quantum Devices, Cheng-Hsiao Wu, Richard M. Williams

Electrical and Computer Engineering Faculty Research & Creative Works

We have used a thermodynamic model to calculate theoretical limiting efficiencies for simple and multiple gap solar cells. The limiting efficiency is 26% for a simple solar cell of hydrogenated amorphous silicon, operating at one Sun sensitivity. For a multiple gap cell made from hydrogenated amorphous silicon, together with a second cell, made from a material with lower band gap, it is 38%. The optimum band gap for the second material is 1.0 eV.

Improved Wavenumber Resolution For Small Arrays, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

The Objective of the Method Described is to Compute the Fourier Transform of a Function of Space and Time with a Significant Improvement in the Resolution of Spatial Frequencies, particularly in the Case of Small Arrays for Which the Size of the Array is on the Order of One Wavelength (Or less). This Improvement is Initially Developed by Considering the Conversion of Spatial Frequency into Temporal Frequency through the Oscillatory Motion of a Single Receiver. a More Practical Scheme is Next Presented in Which the Oscillatory Motion is Created Synthetically by the Appropriate Sequential Sampling of Individual Elements in a …

Bibliography Of Power Systems Operator Training Resources Ieee Committee Report Prepared By The Pes Working Group On Operator Training (Wg78-4), Max Darwin Anderson

Electrical and Computer Engineering Faculty Research & Creative Works

This paper provides a current listing of training courses, programs, and resource materials for Power System Operator/ Dispatcher training. The training resources are subdivided into five (5) categories: I. Dispatcher training courses and facilities developed by the Suppliers/Manufacturers II. University Short Courses III. Conference Publications IV. Reference Books V. Correspondence Courses A brief description of the offerings of each of the Suppliers/ Manufacturers is included. Copyright © 1983 by The Institute of Electrical and Electronics Engineers, Inc.