Engineering Commons^™

A Comparative Analysis Of The Capabilities Of Three Stereo Radar Techniques When Operating In The Presence Of System Errors, George L. Bair

Masters Theses

"Three stereo radar techniques for producing stereo images from which topographic data and maps may be obtained are described and their performance in the presence of system errors is determined. The techniques are: an improved single flight technique which uses a combination of two antenna beam characteristics which permits terrain illumination from nearly the same aircraft position, a previously proposed single flight technique which uses two horizontal linear arrays generating vertical fan beams at different azimuth angles, and an existing two flight technique which uses a horizontal array generating a side-looking fan beam.

Error analyses are performed to determine the …

A Discrete Approach To Surface Interpolation, Jerry Lee Albert Sandvos

Masters Theses

"An equidistant spacing of two dimensional data points is a requirement of most automated analysis routines. In this thesis, a method of generating such equispaced data from randomly spaced data is developed and implemented by a set of computer routines. The method represents the study area as a two dimensional spatial array, in which each array cell represents the data value of a subarea of the study area. A routine sorts and places the data in the array. Missing values in the array are interpolated from nearest neighbors. Filtering is used to smooth errors and a contouring routine is used …

A Digital Simulation Of The Statistical Properties Of Ionospheric Scintillation, William Frederick Deckelman

Masters Theses

"This thesis shows that a bandlimited bivariate-normal time series is a useful model for the envelope of scintillating radio signals traversing the ionosphere. A software computer model is designed and its parameters varied to obtain good fits of the fade duration distribution of the time series generated by the model with that of an actual block of ionospheric scintillation data. The power spectrum of the actual time series corresponding to the in-phase and phase quadrature components of ionospheric scintillation is shown to lie between that of a first- and second-order Butterworth filter through comparison with model generated data"--Abstract, page ii.

Feed-Forward Control Circuit For A Computer Controlled Dc Motor - Ac Generator Set., Richard Allan Smith

Masters Theses

"The current trend of development of generation in electric utility systems is toward complete on-line computer control of real and reactive power generation. In keeping with this trend this work is to design, construct and operate a laboratory model of a computer-controlled power system generator. The equipment design is guided by a desire to allow real time computer control and program assignment of generation levels.

This work is intended as a first step in the development of a complete on-line computer-controlled laboratory model of a power system. It will make possible the study of state-of-the-art methods of operation of power …

An Analysis Of The (N-1,N) Pad ̌Approximant To The Ideal Delay Operator In Terms Of Bessell Functions., Carl Richard Erdmann

Masters Theses

"A realizable, lowpass, non-minimum phase approximation to the ideal distortion less delay operator e^-st₀ is analyzed in terms of the Bessel functions. The characteristics of the first ten members of the approximation are explicitly considered in this paper. The approximation is demonstrated to be realizable for all orders. Amplitude and phase characteristics are described in relation to the ideal delay operator in compact form and in terms of existing ii tabulated functions. Both amplitude and delay bandwidths are characterized by simple and accurate approximations. The maximally flat properties of both amplitude and delay responses are demonstrated. The transient …

Design And Operation Of A System For The Measurement And Display Of A Railroad Train Length., Paul Clement Kriegshauser

Masters Theses

"This thesis describes the design, operation, and application of a system for the automatic measurement of a railroad train length. The system is based on sensing individual wheel crossings with two commercial variable-reluctance wheel sensors. The individual wheels are not counted as they are sensed, instead the system uses the information to compute the train velocity. These sensors are separated a known distance on the railroad track at the location a length measurement is desired. The train may pass these sensors at any desired speed and in either direction. The developed system is not dependent on car length or number …

On The Extension Of The Output Capabilities Of Flowware, A Graphical Interactive Digital System Simulator., R. Dean Delker

Masters Theses

"A research effort which addresses the problem of providing output from a register transfer level digital simulator which allows the user to better understand how his simulated system functions are described. A review of the output capabilities of existing register transfer level systems indicates that a strictly textual output leaves much to be desired, and for that reason, this work concentrates on developing forms of meaningful graphical output displays. This criterion of "meaningfulness" can be considered as a twofold objective to be reached in that the output must both reflect the functioning of the system and be presented in a …

Study Of Techniques For Designing Large Digital Systems Interactively., Harold Dale Puls

Masters Theses

"FLOWWARE [1-4] is an interactive register transfer language based upon the concept of flowcharting. The graphic nature of the language, however, generates a few disadvantages when it is used on a large design. Changes have been made to the basic FLOWWARE package to aid the user in specifying and displaying his design. In addition, responsibility for the design has been shifted to the remote large computer to lessen the size requirement on the local minicomputer"--Abstract, p. ii

High Density Serial Encoded Tape Systems., Billy J. Romine

Masters Theses

"A digital approach to phase lock loop design is presented. Two separate circuits are developed and analyzed. The circuits developed have certain characteristics which can be applied to serial data encoded tape systems. One of the circuits can be expanded into a multiple track configuration with a minimum amount of hardware. The second circuit features a fast initial synchronization method over a wide input frequency range.

The application 0£ the phase lock loops to the retrieval 0£ serial encoded data is investigated. Three representative data encoding methods are considered. The approximate bit density obtainable with each encoding method is calculated …

A Study Of Digital Computer Control Of A Continuous Pulp Digester., Charles Edward Barker

Masters Theses

"Detailed analysis of six basic control loops for a Kamyr continuous digester is described using z- and s- transform methods. An example of a digital computer control system for a continuous digester is also presented"-- Abstract, p. ii

The Investigation Of Video Sensitivity And Data Processing Errors Encountered In An Airborne Receiver, James Lee Hamilton

Masters Theses

"The investigation of video sensitivity and both biphase demodulation and Doppler shift processing errors is performed. The effect of pass band ripple on the noise bandwidth of two pole filters is developed. The effect of feedback on the effective noise figure of a high gain IF (Intermediate Frequency) amplifier is investigated and discussed. An analysis of a limiting amplifier-biphase demodulator circuit is attempted. A computer simulation of this same circuit is also performed and the results are compared to measurements taken in the laboratory. With respect to multipath corrupted input signals, a differential phase shift keyed biphase demodulator is shown …

Graph Model Analysis Of Computer Structures, Ömür Taşar

Masters Theses

"Graph theory is applicable to the solving of problems in nearly every field of scientific study. The purpose of this thesis is to consider its applications in representing and analyzing digital computers. Fundamental graph theory definitions, the types and the properties of the directed graphs, the matrix representation, and several reduction techniques are discussed. The blocking gate method for diagnosing computer systems is described and applied to the Scientific Control Corporation (SCC) 650 for its fault-diagnosis.

Microprogramming has been a significant trend in hardware and software designs of computers. Microprogrammed computers are discussed in comparison to conventional computers. A general …

Computer Analysis Of 3-Phase Induction Motor Operation On An Open-Delta Distribution System, S. Clark Seematter

Masters Theses

"Open-delta/open-delta and open-wye/open-delta transformer banks are often used as an economic means of supplying simultaneous single-phase and 3-phase loads. If the 3-phase load is an induction motor and if these banks are used, the inherent voltage unbalance causes increased losses and uneven heating that may lead to motor failure. Two previously published theories are used to predict motor heating that is caused by the unbalanced voltages and the motor derating that is necessary to prevent insulation failure"--Abstract, page ii.

Investigation Of The Electric Field In The Vicinity Of A Water Drop Adhering To A Conductor, Jamnarn Hokierti

Masters Theses

"Electric field calculations in the vicinity of a conductor above ground are developed with constraints on the distance from the conductor for which the electric field equations can be applied for practical applications. The electric field in the vicinity of a small water drop adhering to the conductor has been calculated. Application of this electric field in the vicinity of the water drop has been used to compute the apparent surface charges and also the forces on the small water drop surface. Methods for the calculation of space charge due to ionization on the water drop has been suggested"--Abstract, page …

Electrical Cable Design And Applications, Robert William Buente

Masters Theses

"The materials available for constructing various electrical cables are discussed, along with remarks/ pertaining to the attributes and limitations of each. The installation and maintenance considerations are discussed in detail. Electrical considerations involved with designing a cable system are outlined with references to their specific application. Special cable constructions, their applications, and their typical modes of installation are reviewed. The conclusion explains an overall cable system design approach along with miscellaneous information"--Abstract, page ii.

Transformer Connection Study For 138 Kv To 12.47 Kv Substations Of The Union Electric Company St. Louis, Missouri, John Glenn Walsh

Masters Theses

"This thesis examines the transformer connections that can be used in the new 138-12.47 kV substations on the Union Electric power system. The object is to determine if a zero phase shift transformer without a delta connected tertiary winding can be used and economically justified. Traditionally a delta winding has been automatically included for this application without taking engineering time and effort to study all ramifications including possible dollar savings available with other connections. Three transformer manufacturers supplied technical and cost data which are analyzed, based on Union Electric system conditions. Consideration of relaying, harmonics and unbalanced loading shows that …

Air Breakdown In A Radial-Mode Focusing Element, Lee W. Casperson, Mohammad Shabbir Shekhani

Electrical and Computer Engineering Faculty Publications and Presentations

A new radial focusing device is described that condenses an incident laser beam to an extremely intense and uniformly illuminated focal spot. The focal region is useful for many applications. When used with a 10.6-µm CO₂ TEA laser source, a disk-shaped air-breakdown spark results, and the properties of this spark have been investigated.

Hall Effect Magnetometer, John A. Woollam, Harry A. Beale, Ian L. Spain

Department of Electrical and Computer Engineering: Faculty Publications

A magnetometer utilizing a single crystal of Bi²Se³ having a rhombohedral crystal structure is described along with a method for making such a device. The Bi²Se³ has a positive or negative Hall coefficient and a carrier concentration of about 10¹⁸to10²⁰ per cubic centimeter.

A High Speed Pulse Code Laser Diode Modulator, John Lawrence Mcdonough

Retrospective Theses and Dissertations

This research report reviews the basics of pulse code modulation (PCM) techniques and includes a special encoder design for a system which uses a laser diode output for the transmitted pulse. The text discusses PCM and its features, PCM formats, synchronization, and various accepted PCM codes. The encode circuit design is complete with a description of the circuit, circuit components, and operation. Included are the necessary diagrams, figures, specifications, and parts list. The transmitted output of the design circuit has a repetition rate of one megabit per second.

Kalman Filter Equalization For Qpsk Communications, Tze-Shen Lee

Doctoral Dissertations

"The discrete complex Kalman filter is considered as an equalizer for quadrature phase shift keyed (QPSK) systems in the presence of additive noise and intersymbol interference (ISI). For a known linear time-invariant channel with finite duration impulse response, the finite n-dimension complex Kalman filter equalizer is able to reduce the degradation caused by ISI. When the channel is unknown, an adaptive Kalman equalizer is used in which the channel complex tap gains are estimated by decision feedback. A two component multipath channel QPSK system is used as an example. Using the Chernoff upper bound to calculate the error probabilities, the …

Surface Elastic Waves In Piezoelectric Semiconductors And Layered Media, Yu-Pin Han

Doctoral Dissertations

"The primary interest of this investigation is to understand the surface elastic wave properties in piezoelectric semiconductors and layered media. Generalized piezoelectric wave equations in piezoelectric semiconductors and layered media are derived. Systems considered are the piezoelectric semiconductor, the two layer piezoelectric insulator-semiconductor, the three layer piezoelectric insulator- gap-semiconductor and the four layer piezoelectric insulator-gap-semiconductor-dielectric substrate. The eigenwave expansion and the iteration methods in the complex domain are used to solve the problems. Mathematically, it represents a solution of the eigenvalue boundary value problem which involves iteration of functions in the complex domain. Solutions obtained are eigenvalues and eigenvectors which …

Parameter Identification Of Nonuniform Distributed Rc Networks, Roger Allen Hayes

Doctoral Dissertations

"The problem of the unique parameter identification of nonuniform distributed RC networks is addressed in this dissertation. Previous literature provides for the equivalence of distributed networks with respect to the terminal characteristics. Therefore, the question is whether unique parameter identification is even possible. This work settles that question by presenting the sufficient conditions to insure a unique solution to the parameter identification problem. One theorem requires the knowledge of a driving-point impedance, the knowledge of the physical length, and the constraint that the r(x)c(x) product remains constant to insure uniqueness of the parameters r(x) and c(x). Relaxation of the r(x)c(x) …

Thermal Oxidation Of Gallium Arsenide Phosphide., Leo Edward Coerver

Electrical and Computer Engineering ETDs

This work covers the most important basic facts about the thermal oxidation of gallium arsenide phosphide. The work is confined to lightly dopes GaAs(1-x)^px material with a phosphorus mole fraction of 0.50+-0.02. All oxidations were carried out in open tubes and consequently at atm

ospheric pressure. Initial studies over a wide range of oxidation temper­atures showed that serious surface damage to the semiconductor surface occurred if the oxidation temperature was greater than 700° C. An anneal in an inert atmosphere at a temperature no greater than 700° C for at least 90 minutes was required to obtain good pinhole-free dielectrics. …

Electron Beam Evaporated Aluminum Oxide Gate Silicon Transistors., Chang-Ching Cheng

Electrical and Computer Engineering ETDs

Aluminum oxide films prepared by the electron beam evaporation of Al2O3 tablets have been studied in metal-insulator-semiconductor devices. The structure of Al2O3 films is amorphous with a density os 2.25 gm/cm3. The film conductivity is smaller than 5x10^14 (ohm-cm)^-1 and the breakdown strength is higher than 1.3x10^6 V/cm. The transport mechanisms in the film are believed to be impurity-induced flow at room temperature and Poole-Frenkel emission at higher temperatures.

The average relative dielectric constant is about 7. The interface surface states of the MIS sample are small in the middle of the forbidden band, gradually increasing toward the band edges. …

Dynamics Of Interconnected Systems With Pulse Frequency Modulators, Halil Ozcan Gulcur

Dissertations

The objective of this dissertation is to study the dynamics of systems consisting of interconnections of an arbitrary number of complete-reset pulse frequency modulators (CRPFM's) and linear dynamical subsystems (in general, time-varying, lumped and/or distributed). CRPFM, which represents a generalization of several types of pulse frequency modulators (PFM's), consists of two basic components; a multi-input dynamic element, called the timing-filter (TF) and a threshold device (TD). Whenever the output of the TF reaches a given threshold value the TD generates an impulse and, at the same time, resets all the states of the TF to zero. This dissertation is devoted …

Energy States In Random Media., Peter Chen-Chi Chang

Electrical and Computer Engineering ETDs

This dissertation is concerned with energy levels and the density of states in random crystals.

By developing a non-linear differential equation for the phase process in random crystals, it is shown how to calculate the density of states in one-dimensional random arrays. The method used ha􀀕 the virtues of simplic­ity and, where comparison with previous numerical results can be made, accuracy, with minimal computing time. Various analytical results are found with the phase process method and these are equivalent with results found by other workers.

In the three-dimensional case, it is shown how to use the phase process to help …

Gaussian Light Beams In Inhomogeneous Media, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Vector wave solutions are obtained for the propagation of beams of light in media having slow spatial variations of the gain, loss, or index of refraction. The formalism developed here is applicable to a wide range of problems, and an exa mple considered in detail is the propagation of off-axis beams in lenslike laser materials and optical waveguides. A procedure is also described for the diagnosis of localized dielectric inhomogeneities such as plasmas by means of Gaussian laser beams.

Correlation Of Drain Breakdown With Excess Noise And Other Surface-Related Phenomena In Enhancement Mosfets, Jerry J. Rij

Theses

An investigation of semiconductor surface-related phenomena has been undertaken to correlate 1/F noise with drain breakdown in P-channel enhancement MOSFET's. Increases in the intensity of drain current fluctuations at 10Hz and at 1KHz, particularly at the higher frequency, was observed following accelerated life-testing for threshold voltage drift. It was also concluded that mobile ions near the oxide-semiconductor interface produce a sharp increase in fast trapping centers. It was also found that 1/F noise intensity consistently peaked at the threshold of drain breakdown and that it steadily decreased with further increases in drain current. Of all the transistors tested, those with …

Non-Transposing Mute, Benjamin R. Gossick, Karl A. Schneider

Electrical and Computer Engineering Faculty Patents

A non-transposing mute having a metallic hemispherical resonator with a hollow acoustic filter attached thereto is provided for detachably fitting upon the rim of a brass musical instrument. A variety of tonal quality is available by choice of the particular filter selected by the musician.

Memory Utilization For A Dynamically Microprogrammed Computer, Paul D. Stigall

Electrical and Computer Engineering Faculty Research & Creative Works

A Particular, Dynamically Microprogrammed Computer (Proposed by Tucker and Flynn in Commun. of ACM, April 1971) is Considered with Respect to Main Memory and Micro-Memory Utilization. a Dependency is Shown between Memory Utilization and Utilization of the Arithmetic and Logic Unit.