Digital Commons Network^™

The Design And Construction Of A Medium Power, Synchronous, Electronic Switch, Floyd S. Hall

Masters Theses

"This paper presents the design and construction of a medium power, synchronous, electronic switch and associated timing and control circuits.

The unit described is capable of controlling a 20 ampere resistive or inductive load from a 110/220 volt, 60 Hz excitation source. Thyristors are used as the active switching elements. The period of the on/off switching cycle may be varied from 1/60 second to 8 1/2 seconds. Turn-on and turn-off may occur at independently selected phase angles relative to the reference frequency source.

Higher power operation could be obtained easily with minor design changes"--Abstract, page ii.

Design Of Non-Uniform Linear Antenna Arrays With Digitized Spacing And Amplitude Levels, Jack F. Morris

Masters Theses

"Recent developments in space exploration have shown a need for high resolution, high gain antennas. The introduction of non-uniform linear array theory has provided a means by which arrays may be designed to produce narrow main beams with fewer elements than required by uniform arrays. A general theory has not been developed, however, and the design engineer has been left with only trial-and-error methods with which to work. In this study a technique has been developed by which non-uniform antenna arrays may be synthesized to meet a given set of specifications with reasonable accuracy. The elements of the array are …

Design Of A Photoelectric Transient Torque And Speed Meter, Raojibhai A. Patel

Masters Theses

"There are many situations in which it is desirable to know the speed of the shaft and the torque it is transmitting, when it is equally undesirable to make any mechanical connection to the shaft. This thesis describes the development and design of a device for measuring the torque and speed by photo-electric means. The basic principle is that a light beam parallel to the shaft may be used to pick up the desired information without adding friction to the system. The deflection of a torque tube inserted in the shaft opens or closes a set of apertures arranged in …

Optimum Finite Memory Nonlinear Filter, Ching-Chyoun Yang

Masters Theses

"This thesis investigates the possibility of using the Zadah theory and a machine type computer to design an optimum finite memory nonlinear filter for extraction of Poisson distributed signal pulses from a background of Gaussian noise. Basically the procedure involves the technique of solving simultaneous equations by the computer. We demonstrate that it is possible to find the limitation of the filter of class N₁ in terms of an absolute minimum mean square error. However, due to the capacity of the computer we do not actually determine the absolute minimum. Nevertheless we do show that the mean square error decreases …

Measurement Of Stray Load Loss Of D.C. Machines, Kanaiyalal Ramanlal Shah

Masters Theses

"For many years the standard practice, in calculation of conventional efficiency of d.c. machines, has been to include stray load losses as equal to 1% of the output. This assumption may be true for large, compensated d.c. machines but it is known to be small for smaller, uncompensated, general-purpose, industrial-type machines of open design. An A.I.E.E. Committee on Rotating Machines was formed to investigate whether the present practice of assigning 1% for the stray load loss is justified or not. They reached a conclusion, reported in 1949, after investigating 243 stray loss tests on different motors ranging from 1/2 hp …

Equivalent Circuit Of Unsymmetrical Inductance Diode Using Linvill Lumped Model, Donald Lawrence Willyard

Masters Theses

"Integrated circuit techniques and applications are rapidly changing the electronics industry. A problem common to both state-of-the-art approaches to integrated circuit fabrication is that of miniaturizing and integrating inductors. It is found that, for a certain range of injection current levels, certain unsymmetrically doped junction diodes have an inductive small-signal impedance. This thesis discusses the theory of inductance diodes and applies finite difference equations and the Linvill lumped model to the differential equations that describe their carrier flow processes. The static I-V characteristic and the small-signal equivalent circuit at high injection densities are derived. The elements (R,L,C) of this equivalent …

Stability Determination By Liapunov's Method In Nonlinear Control Systems, Neng-Chung Liao

Masters Theses

"An introduction to Liapunov's second method as it applies to control system stability is presented in this work. Main theorems and definitions of Liapunov's method are treated. In particular, Lur'e's method and Szego's method for testing the stability of a nonlinear system are presented, and several examples are used to illustrate these procedures"--Abstract, page ii.

An Evaluation Of Demonstrations On Inductor Theory, Boyd Warner Wasson

Dissertations and Theses @ UNI

The writer sought an improved approach for teaching theory of electronics to high school students. This approach was intended to require less expense and time needed to provide classroom instruction on electrical theory.

The purpose of this study were to:

(1) Prepare a number of demonstrations to illustrate phenomena associated with coils or inductors and their use in practical electronics.

(2) Prepare equipment and gather parts needed to perform demonstrations. Ease of construction and economy were important considerations.

(3) Evaluate the effectiveness of the demonstrations on student comprehension and the ability to apply information taught.

Thin Film Resistor Deposition, Rollie R. Herzog

Masters Theses

"Thin film techniques may be the key to future miniaturization of electrical equipment. The purpose of this thesis was to develop procedures for deposition of thin film resistors and to test these deposited resistors. Starting with a vacuum system, equipment was designed and built to hold and heat the substrate, monitor the substrate temperature and deposited resistance, and to evaporate the material to be deposited. Resistors were deposited and tested for resistance between resistors, capacitance between resistors, and resistance of resistors. A heat aging test was also used comparing resistors with and without a silicon monoxide coating"--Abstract, page ii.

Linvill's Model As Applied To P-N Junction Photo-Diodes, Rudy Michael Chittenden

Masters Theses

"The problem undertaken in this study is to present a performance evaluation of Linvill's model as it pertains to the p-n junction photo-diode. The evaluation is performed by comparing the distributed mathematical solutions, the solution obtained using Linvill's lumped model, and the experimental measurement of the transient voltage rise across a photo-diode due to a unit-step pulse of light incident on the junction. Despite the absence of a suitable light source for use in the experimental measurement, it is concluded that Linvill's model provides an excellent means to determine the risetime of a photo-diode. This is provided that the photo-diode …

On Optimum Receiver Using Decision Theory, Philip T. Tai

Masters Theses

“In recent years communication engineers have given increased attention to the study of communication through random media. The name random is used to describe a medium the properties of which are stated only in a statistical sense. For example the impulsive response of a certain medium may only be known as one of an ensemble of possible impulsive responses; the particular member of interest being drawn up according to some statistical rule. In other words there exists some "uncertainty" concerning the characteristic description of the medium. Significant work on these problems has been done by Price and Turin. Related work …

The Resolution Of Two Known Signals In White Gaussian Noise., Peter Cheng-Fang Wang

Masters Theses

"The problem of resolving two signals F1(t) and F2(t) in white Gaussian noise n(t) is treated here as a problem in statistical decision theory. We assume a situation in which one of two similar signals is present and an observer is asked to make a decision concerning which of the signals is present with a tolerable probability of error. The observer is allowed to use the best system which he can design for this particular purpose. Of course, this observation will be disturbed by noise and therefore, the observer is led to ambiguous selections. It is apparent that the optimum …

Time Optimum Switching Zones In Multiple-Valued Control Systems, Jack Leroy Crawford

Masters Theses

"Present control system theory provides the criteria necessary to bring a second-order single-valued system to rest in a minimum time after a step input. The bang-bang type controller has been developed to obtain this optimum response.

However, existing theory fails to provide the necessary information to obtain the optimum response from a second-order rotational system when multiple values of angular position are allowed. This thesis extends the control theory to include these multiple-valued systems by showing the existence of what are called optimum switching zones. These zones predict which of the infinite number of switching curves in a multiple-valued system …

Optimalization By Peak-Holding, Curtis W. Dodd

Masters Theses

"The problem presented is a study of the peak-holding method of optimalization. This method applies to a system that has an extremum.

After describing how the complete system, consisting of the controller and the controlled system, works; variations in the controller are presented. These variations are changes in the final stage of the controller, the servo. A phase-plane analysis shows how the output of the controlled system varies with its rate of change. Limitations are presented which tell why the system cannot be kept at its peak value at all times. Finally an analog simulation is used to study the …

An Analysis Of The Simulated Inductande Obtained From Forward Biased Semiconductor Diodes., Everett Harold Vannoy

Masters Theses

"The problem undertaken in this thesis is to study the simulated inductance observed in forward-biased abrupt junction p-n diodes with a highly doped p region and a nearly intrinsic n region and show that it is due to conductivity modulation. Unlike other analyses of this phenomenon, a voltage step is applied to the diode in such a direction as to forward bias it and the behavior of the injected minority carriers are observed. By comparing the resultant current through the diode to the relationship predicted by the equivalent circuit of the diode, an expression is obtained for the simulated inductance. …

High Order Bang Bang Control System., Shing-Chou Pi

Masters Theses

"The problem undertaken in this thesis is to find a representation of a nonlinear controller to minimize the response time of a limited input plant whose transfer function has N negative real poles. The extension of the phase-space method to automatic control systems described by high-order differential equations with a general high-order input is considered.

The design utilizes a maximum effort controller whose switching time is determined by the concept of switching hypersurfaces of the system in N-dimensional phase space and the concept of a distance function, which is & geometric length between the initial state point and the switching …

A Study Of Certain Atmospheric Effects On Radar Accuracy, Kenneth R. Swimm

Electrical and Computer Engineering ETDs

Along with other factors, accurate radar target location is dependent upon a knowledge of the electromagnetic propagation path. The propagation path is a function of the characteristics of the medium through which the signal travels. Advances in the resolution capabilities of modern electronic tracking equipment have led to requirements for more accurate prediction of atmospheric refraction characteristics. The inherent error of the equipment is, in many cases, less than the error introduced by the atmospheric refractive effects. After corrections to observed launch angle and target range have been made on the basis of atmospheric refraction information, residual errors in range …

A Five Dimensional Field Theory., Scott Holzhauser

Electrical and Computer Engineering ETDs

Several authors in the past have utilized the five dimensional manifold to accomplish their ends, as the next few sections explain. The ends are frequently different, however, Corben1,2 relates his fifth dimensional variables to rest quantities, such as the "rest mass density" and "rest charge density." Flint3,4,5 uses x as an unobservable 5 cyclic coordinate, and Ingraham6 interprets x as a "parameter of finiteness" that keeps finite the usual field quantities.

A Time Optimum Bang Bang Control System Under Specified Inputs., John F. Curtin

Masters Theses

"The problem presented is a study, by simulation on an analog computer, of a time optimum "bang bang" control system with a second order plant. Phase plane analysis techniques are used to describe the performance of the second order plant under the action of a maximum effort controller. From this, the system logic is developed for time optimum response to a step reference input. A fast time model of the plant is used to obtain repeated high-speed extrapolations of the plant outputs, at the same time a linear predictor generates future values of the reference. The error functions thus found …

Determining Design Freedom Of Linear Feedback Control Systems, Harley D. Brixey

Masters Theses

“The problem confronted in this thesis is to develop a method or procedure to be used in determining the amount of design freedom that is available in any given linear feedback control system by working with the signal flow-graph representation of the system.

Literature was reviewed that deals with basic signal flow-graph theory and degrees of design freedom. Signal- flow-graph theory that forms a foundation for the development is presented.

The development consists of starting with an essential signal-flow graph of order one. The sensitivity and transmittance functions are written for this essential graph in terms of graph symbols; then …

A Graphical Solution Method For The Tchebychev Elliptic Function Filter, Gene S. Luckfield

Masters Theses

"This thesis is concerned with the design of the Tchebychev elliptic function filter. The Darlington synthesis procedure is discussed and salient points from Darlington's paper needed for the design of this filter are presented.

It is shown that the design of the Tchebychev elliptic function filter requires a knowledge of the elliptic functions, particularly the elliptic sine. Since the use of these functions is not common, a brief review of their properties is presented.

Using the elliptic functions, a development of the equations describing the behavior of the Tchebychev elliptic function filter is given for the case of a normalized …

An Approach To Azimuth Angle Refraction Corrections, Wallis R. Cramond

Electrical and Computer Engineering ETDs

In the past, analyses of tropospheric reactions of electromagnetic waves propagating in the atmosphere have been based on spherically symmetric medium. However, this applies only to ray bending in a vertical plane (elevation angles). Numerous methods have been developed to correct for elevation angle errors. In 1961, the presentation of a new method for use in a nonsymmetric atmosphere revived interest in horizontal (azimuth angle) bending. In order to use this method to test significance of azimuth angle errors, the spacial distribution of index of refraction must be known.

The primary objective of this paper is to propose a model …

A Study Of A Second-Order Predictive Control System, Tarkeshwar Singh

Masters Theses

"The purpose of this thesis is the study of a predictive control system by simulating it on an analog computer. Logic criteria for step reference inputs are derived by the phase- plane technique, and tie corresponding logic network designed to bring the error and error rate of the controlled system toward zero in the least possible time.

The responses of the predictive control system for step, ramp, sinusoidal and exponential reference inputs are investigated with primary emphasis placed on the rise time and overshoot for several values of step inputs of the reference.

Finally, recommendations are made for further investigations …

A Comparison Of A-C And D-C Lead Compensation From D-C Prototype Networks, Piyush Parikh

Masters Theses

"The object of this thesis is to study the difference in transient and frequency response characteristics between a prototype d-c phase lead compensating network and an equivalent a-c phase lead compensating network.

A second order servo is selected to be compensated and five d-c prototype and equivalent a-c phase lead compensating networks are designed. The frequency characteristics of the a-c networks are obtained experimentally and these of the d-c networks are obtained analytically. The characteristics of both networks are compared and their differences are studied. The transient characteristics of the d-c and a-c compensated closed-loop systems to a step input …

A Radar Refraction Correction For Symmetric And Nonsymmetric Tropospheric Index Distributions, Ralph J. Rainey Jr.

Electrical and Computer Engineering ETDs

The high precision radars now in use have demonstrated the need for more exact refraction correction than is afforded by any fixed "standard" refractive index profile. The precision capabilities are even substantial enough to cause concern over the possible effects of the non-symmetric index distribution which introduces azimuthal errors. However, the indications are that the present limitation on true range measurements are primarily due to limitations on the radar itself, and a "gross" average correction is adequate for many cases of interest.

A Study Of Viscous Frictional Effects And Relay Characteristics On The Operation Of A Positional Relay Servomechanism, Earl F. Richards

Masters Theses

"The thesis describes some experimentally observed data and analytical approaches to the study of a relay servomechanism. The experimental data were secured from an analog simulation of a relay servo system. The results of this data were compared to the transient approach by use of the phase-plane method. The stability of the system was determined using a describing-function. The analytical approaches are described in the presentation.

A study of the effects of viscous friction is described, and the characteristic of the relay used in the system is given special attention. The response to input driving function was considered, and rise …

Design Of An Intermediate Frequency Amplifier And Variable Frequency Oscillator, Robert Charles Mcintyre

Masters Theses

"Since the advent of the transistor in 1948 many technological barriers have been overcome in the field of semiconductors. Unfortunately, however, there is a considerable period of time between the discovery of a scientific phenomena and its widespread use and understanding by practicing engineers. The motivating factor which prompted this investigation was primarily the lack of knowledge which the author possessed concerning transistors. The selection of the amplifier and oscillator design confined the study primarily to the transistor. Considerable time, however, had to be spent in the study of basic transistor theory before any phase of the design could be …

The Equalization And Optimization Of A Third-Order Type-1 Position Control System, Viswanatha Seshadri

Masters Theses

"While the practice of feedback control dates back to the day when the earliest living organisms began to react to their environmental conditions and the changes therein, it has been only during the past two decades that this technique came to be subjected to a scientific examination. Yet, an astoundingly rapid advancement has resulted in the field of servo-mechanisms, contributing substantially to the development of modern civilized existence and activity to its present standards, and promising to contribute, to an ever-increasing extent, to the accelerated progress of scientific and industrial enterprise in this space age.

The principal concerns of the …

A Method For The Prediction Of Detection Ranges For Pulsed Doppler Radar, Phillip Orlan Brown

Masters Theses

"Modern radar systems must provide greater detection ranges both against high and low altitude targets because of the significant advances in weapon speed and range. Extended range indicates that the power transmitted by the radar must be increased. It follows, that ground return becomes a problem even at high altitudes.

There are at present three basic types of radars which are (1) pulsed, (2) continuous wave, and (3) pulsed doppler radar. The conventional pulsed radar now closely approaches the theoretical optimum performance; however, it does not have the inherent ability to distinguish between ground return and moving targets. The continuous …

Analysis And Synthesis Of A Current Regulator System, William P. Aiello

Electrical and Computer Engineering ETDs

This report describes a practical current regulator system used to accurately control the current delivered by a 500 kilowatt motor-generator unit. The generator supplies its current of 2000 amperes at 250 volts to a large water-cooled air-core solenoid used by LASL Group P-7 for experiments in connection with the Sherwood program.

After a general discussion of the system specifications and the basic regulator loop, each of the components in the basic regulator loop is described in considerable detail. The description, in most cases, is mathematical in nature although many circuit diagrams are included with brief descriptions when necessary for proper …