Digital Commons Network^™

Moment Method Solution Of The Time-Dependent Transport Equation To Describe The Scattering Of Gaussian Plane Wave Pulses By A Forest, Nack Yang Cho

Theses

The time dependent transport equation is used to study the transmission of periodic pulses through a forest. The forest is assumed to occupy a half-space region, to be statistically homogeneous and to scatter energy isotropically A periodic sequence of Gaussian plane wave pulses is assumed to enter the forest normally from free space. The transport equation is solved by the moment method using triangular expansion functions. Numerical results indicate the dependence of the incoherent intensity on penetration depth, observation angle, albedo and pulse repetition rate.

Considerations In Developing And Utilizing Operator Training Simulators, T. E. Dyliacco, M. K. Enns, J. D. Schoeffler, J. J. Quada, D. L. Rosa, C. W. Jurkoshek, Max Darwin Anderson

Electrical and Computer Engineering Faculty Research & Creative Works

Effective electric system operation depends on strengthening the relationship between the system operator and the electrical system with its associated control system. This relationship can be developed through a training medium which increases the operator's knowledge of the behavior of the power system under various operating conditions and contingencies, and its response to control actions. An Operator Training Simulator (OTS), which simulates the static and dynamic responses of the operator's power system and his control system, can accomplish these training objectives. The concepts developed in this paper are based on the work of the project team through funding by the …

Electrical Engineering, C. J. Thomforde

UND Departmental Histories

This departmental history was written on the occasion of the UND Centennial in 1983.

Microcomputer Control Of A Model Robot System Using Programmable Pulse Width Modulation, Richard Eugene Wainwright

Masters Theses

"The hardware design of a model robot system for experimentation in microcomputer control is presented. A special interface board is designed to allow an Apple II Plus microcomputer to control a model robot system which consists of a three-jointed robot with an electromagnet end effector and a conveyor belt, with an optional vision system. A programmable pulse-width modulator is designed to drive the DC motors which operate the robot and conveyor belt. Improvements and additional uses for the model system are discussed"--Abstract, page ii.

Error Detection For Data Communication Systems, John Biancamano

Theses

A description of the problems encountered in the data communications field and the various solutions can be found in a number of diverse, and often theoretical sources. My intention in writing this thesis is to bring together, in a practical and understandable manner, the theory and the application of a method of error detection used extensively in data communication systems known as the Cyclic Redundancy Check (CRC).

To provide some background on the subject, a description of a data communication system is presented, and the possible sources of error are explored in some detail. Data transmission formats are described, and …

The Performance Of Full Response Multi-H Modems In Practical Environments, Mark Alan Wickert

Doctoral Dissertations

The power and bandwidth efficiency of multi-h continuous- phase modulation (CPM) schemes in practical environments are considered. Specific impairments considered are transmitter filtering, amplitude limiting, and receiver symbol timing, phase error, and decision depth sensitivities. A coherent receiver model is employed which uses the Viterbi algorithm (VA) to perform maximum likelihood sequence estimation. For (2/4,3/4), ll (3/8,4/8) and (4/8,5/8) linear phase codes, a signal-to noise ratio (SNR) power gain of 1.85 dB, 1.9 dB, and 2.4 dB at a bit error rate (BER) of 10^-5 over differentially coded minimum-shift keyed (MSK) modulation are obtained, respectively. With transmitter filtering the …

Line-Adaptive Hybrid Coding Of Images, Tai On Tam, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Describes Novel Adaptation Strategy for Hybrid Transform/DPCM Image Coders. This Strategy Has Yielded a 2–8 DB Increase in Signal-To-Noise Ratio in the Transmission of a Head and Shoulders Image at Bit Rates of 1–4 Bits Per Pel and One-Dimensional Transform Block Sizes of 2–16. © 1983 IEEE

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 …

Estimation Of Ocean Wave Wavenumber And Propagation Direction From Limited Synthetic Aperture Radar Data., Gordon E. Carlson

Electrical and Computer Engineering Faculty Research & Creative Works

A method for estimating wavenumber and propagation direction for the dominant wave component in an ocean wave field from a few scans of synthetic aperture radar data is described and analyzed. The use of just a few radar scans rather than a complete image reduces data storage requirements significantly. The analysis shown uses actual synthetic aperture radar data and provides parameter tradeoffs and statistical performance results. While reasonable estimates of wavenumber and propagation direction are achieved in some cases, the estimates are not sufficiently consistent to be satisfactory over a wide range of cases. The primary problem is one of …

Subharmonic Generation By Resonant Three‐Wave Interaction Of Deep‐Water Capillary Waves, Partha P. Banerjee, Adrianus Korpel

Electrical and Computer Engineering Faculty Publications

Subharmonic generation has been observed during the propagation of deep‐water capillary waves. The observations are shown to be in agreement with the theory of degenerate resonant noncollinear three‐wave interaction in a nonlinear, dispersive medium.

Coherence Effects In Synchronously Pumped Mode‐Locked Dye Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

A formalism is developed for describing the evolution of picosecond mode‐locked pulses in synchronously pumped dye lasers. The finite phase memory of the molecular wave functions is included, and it is found that the resultant coherence effects can be dominant for operation close to exact synchrony. Considerations of the isotropic molecular orientational distribution and the finite vibrational relaxation times are also essential in obtaining quantitative agreement with experimental results.

Adaptive Delta Modulation, Aliuddin Ahmad

Theses

The objective of this thesis is the study of the performance of instantaneously companded adaptive delta modulation (ADM) systems in comparison with linear delta modulation (LDM) in terms of signal to quantization noise ratio (SNR). Various schemes for ADM are discussed and their advantages and disadvantages are indicated. SNRs are calculated by simulation, with IBM's continuous system modeling programming (CSMP) language being used as a tool for simulation. LDM, first and second order constant factor delta modulation (CFDM), has been simulated and responses for different types of input signals are presented.

Remote Attitude Measurement Techniques, Frank John Elmer

Dissertations

A method has been developed for solving practical problems which can be expressed in terms of physical geometry. These problems often involve combining directional information observed by remotely located sensors reported in their own respective local coordinate systems. To transform this information into a common coordinate system, the attitude of the sensors must be measured with respect to this common coordinate system.

Physical geometry is a generalization of mathematical -geometry where objects define the endpoints of figures composed of ensembles of lines. A probabilistic approach has been taken which is based on the fundamental assumption that the objects can be …

Pattern Generation And Fault Detection In Digital Circuits Using A Microprocessor, Syed Riffat Ali

Theses

The main object of this Professional Project was to establish a microcomputer based system which could detect faults in digital circuits. Hardware and software for the Motorola 6800 microcomputer system was fully developed. Node level diagnostic programs were then used to pump known "Bit Patterns" into digital circuits and responses recorded via Pseudorandom binary sequence generator using CRC code. This method also known as "Signature Analysis" was then applied to detect faults successfully in Universal Asynchronous Receiver Transmitter or UART Circuits.

Efficient Infrared Upconversion In Gap, M. A. Gundersen, T. A. Yocom, P. G. Snyder, P. F. Williams

P. F. (Paul Frazer) Williams Publications

Mechanisms for linear conversion of infrared to visible were investigated in extrinsic Gap. Efficient (1 %) conversion of 10 micron to visible was observed in GaP:Zn,O. Several device applications are discussed and a quantum counter scheme involving 111-V photocathodes is presented.

Generalized Running Discrete Transforms, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Introduces a Generalized Running Discrete Transform with Respect to Arbitrary Transform Basea, and Relates the Generalized Transform to the Running Discrete Fourier Z and Short-Time Discrete Fourier Transforms. Concepts Associated with the Running and Short-Time Discrete Fourier Transforms Such as 1) Filter Bank Implementation, 2) Synthesis of the Original Sequence by Summation of the Filter Bank Outputs, 3) Frequency Sampling, and 4) Recursive Implementations Are All Extended to the Generalized Transform Case. a Formula is Obtained for Computing the Transform Coefficients of a Segment of Data at Time N Recursively from the Transform Coefficients of the Segment of …

A Performance Study Of 16-Bit Microcomputer-Implemented Eft Algorithms, Paul D. Stigall, Rodger E. Ziemer, L. Hudec

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A Control Program And Operating System For A Three Joint Robot Arm On An Apple Microcomputer, Eric Henry Stelzer

Masters Theses

"A Robotics Operating and Control System for a three-joint robot arm model is presented. The general operation of the system in interfacing the robot to the operator is discussed. Kinematic equations for the robot are derived and commands available to the operator are covered in some detail. The operation of the Control System in moving the robot is explained. Finally, suggestions are made for further development of the system"--Abstract, page ii.

Conversion And Matched Filter Approximations For Serial Minimum-Shift Keyed Modulation, Carl R. Ryan, James H. Stilwell, Rodger E. Ziemer

Electrical and Computer Engineering Faculty Research & Creative Works

Serial minimum-shift keyed (MSK) modulation, a technique for generating and detecting MSK using series filtering, is ideally suited for high data rate applications provided the required conversion and matched filters can be closely approximated. Low-pass implementations of these filters as parallel inphase-and quadrature-mixer structures are characterized in this paper in terms of signal-to-noise ratio (SNR) degradation from ideal and envelope deviation. Several hardware implementation techniques utilizing microwave devices or lumped elements are presented. Optimization of parameter values results in realizations whose SNR degradation is less than 0.5 dB at error probabilities of 10-6. © 1982 IEEE

Applying Software Complexity Metrics To Program Maintenance, Kenneth Magel, Raymond Michael Kluczny, Warren A. Harrison, Arlan R. Dekock

Business and Information Technology Faculty Research & Creative Works

No abstract provided.

Polarimeter, Rasheed M.A. Azzam

University of New Orleans Patents

To measure characteristics such as density and particle-size distributions of a medium that interacts with light, a polarimeter simultaneously develops all 16 elements of the Mueller matrix by modulating polarized monochromatic light with a quarter-wave retarder operating at a predetermined frequency before transmitting it to the medium and then modulating the light leaving the medium with another quarter-wave retarder which operates at a frequency five times that of the predetermined frequency of modulation of the light transmitted to the medium. The light is electrically detected and provides a signal which may, by Fourier analysis, be broken into 25 terms. The …

Explicit Determination Of Thickness Of A Transparent Film On A Transparent Substrate From Angles Of Incidence Of Equal P And S Reflectivities, R. M.A. Azzam

Electrical Engineering Faculty Publications

No abstract provided.

A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

The present thesis attempts to give a concise and critical account of the evolution of the echo phenomena over the last thirty years. Starting with spin and photon echoes, which were among the earliest to be observed and studied, the thesis explores the experimental findings and the models proposed in connection with the more contemporary echo experiments, viz. those involving electroacoustic or polarization echoes in single and polycrystalline piezoelectric materials and in powders. Although the investigations regarding the various mechanisms of short and long term echo formation are by no means complete, a coherent picture is beginning to emerge as …

Laser Broadening Ratio From The Multimode Oscillation Threshold, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Lasers with mixed line broadening typically oscillate in a single longitudinal mode for excitation levels only slightly above threshold. At high pump levels, less desirable multimode oscillation may sometimes occur. A procedure is described for using the multimode threshold as a sensitive measure of the broadening ratio, and GaAs is mentioned as an example.

Fast Transient Contingency Evaluation In Power Systems, Rodrigo S. Chamorro, Max Darwin Anderson, Earl F. Richards

Electrical and Computer Engineering Faculty Research & Creative Works

The problem of creating a practical computational tool to perform transient contingency analysis in a power system control center is considered. The computer program developed may be used in a control center computer where a state estimation program or a consistent set of load flow data is available. It can be run on a periodic basis over a previously specified contingency list, or it can be called by the system operator to analyze a particular contingency. The transient behavior of the system is evaluated based on a simulation technique widely acknowledged for its fast solutions. The method uses rapidly convergent …

The Design And Development Of A Human Interface For An Intelligent Terminal For A Process Control Industry, V. Rangarajan

Masters Theses

"A complete description of an intelligent Terminal to be used in a Process Control Industry is presented. The system software is discussed. An account of the hardware and software interfaces for the input devices, along with the description of the input devices, is included. The data base used in the system is described with an example. Future enhancements have been proposed."--Abstract, page iii.

Chemical Spray Pyrolysis Of Cadmium Telluride., Alok K. Berry

Masters Theses

"Chemical spray pyrolysis is a technique for film growth which is of interest because of its potential for very large scale, inexpensive production of polycrystalline thin film semiconductor materials. Cadmium telluride shows promise as a base material for solar cell applications. Thin films of CdTe have been spray deposited on glass substrates from an aqueous solution containing CdC1₂, Teo₂ and a reducing agent. The films show a zinc blende structure and appear to be intrinsic. Microprobe analysis indicate an excess of Cd, but this is not detectable by X-ray diffraction. The photo absorption studies indicate a direct …

A Performance Study Of A Microcomputer-Iimplemented Microcomputer-Implemented Fsk Receiver, Paul D. Stigall, Rodger E. Ziemer, Van T. Pham

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

High Resolution Laser Absorption Spectroscopy Of Ozone Near 1129.4 Cm-1, Lawrence N. Majorana

Physics Theses & Dissertations

A Beer's Law experiment was performed with a tunable laser to determine self broadened line shape parameters of one infrared absorption ozone line in the v1 band for ten pressures from 0.26 to 6.29 Torr at 285K. SO₂ line positions were used for wavelength calibration. Line shapes were iteratively fitted to the Voigt function at a Doppler width of 29.54 MHz (HWHM) resulting in values for the integrated line• strength, ( S), of (0.144 +/- 0.007 ) x ·10^-20 cm-1/molecule cm-2, line center frequency, (υ_ο) of 1129.426 cm-1 and the Lorentzian contributions to half width, (α …

A Dimensionality Reduction Algorithm For The Karhunen Loeve Transform, Salomi T. Charalambous

Computational Modeling & Simulation Engineering Theses & Dissertations

The Karhunen Loeve Transform has conclusively been shown to be the optimum data compression algorithm for signals belonging to the same second order stationary process. Consequently, researchers have been searching for a fast implementation for the transform. Fast imple­mentation methods similar to those developed for other orthogonal transforms are generally not applicable to the Karhunen Loeve Transform (KLT). Also, since the basis vectors composing the transformation matrix of the KLT are the eigenvectors of the covariance matrix of the input process, they must be computed first. The research re­ ported here is an attempt to reduce the dimensionality of the …