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A Method For Approximating A Specified Impulsive Response, Charles A. Gross

Masters Theses

"Given a system's time response, y(t), to a unit impulse, a method is presented by which an approximating function y*(t) may be determined. It is inherent in the method that the transform function Y*(s) is rational. The poles of the approximating function are found from the coefficients of a difference equation, which is made to fit the given data in a least mean square error sense. The zeros are determined by a procedure based on the fact that at a given time the given function and its approximate derivatives are known. Accuracy and implementation of the method are investigated primarily …

Phase And Amplitude Distributions Of An Unsymmetrically Fed Ground Plane Aperture, Leslie Blumberg

Masters Theses

"An anechoic chamber for use in the B-12 KHz range was designed and built for the purpose of obtaining the far field patterns of antennas and radiation systems. This chamber was evaluated and compared with various types of anechoic chambers from the standpoint of their "room performance."

The anechoic chamber is essentially a room lined with absorbing material, effective at microwave frequencies. The purpose of the absorbing material within the room is to present the reflection of the energy incident upon the walls of the room.

Measurements of the far field radiation pattern of an aperture in a ground plane, …

The Effect Of Non-Linearity On A Frequency-Modulated Wave, Tzu-Tien Hung

Masters Theses

"A method is presented for finding the effect of a nonlinear characteristic of a device on a wave which is frequency modulated by only one sinusoidal modulating wave. The distortion in the output has been found by passing a frequency-modulated wave (which is represented by a summation expression for the spectrum components) through a non-linear circuit having a Fourier series represention of its Characteristic. Two cases have been considered: (1) a nonlinear output-input characteristic, and (2) a non-linear amplitude-frequency characteristic"--Abstract, page ii.

Some Effects Of A Non-Uniform Specific Charge Upon Space Vehicle Parameters, Geary L. Leger

Masters Theses

"An equation is derived for the space-charge-limited current of an ion beam when there exist n different species of ions in the beam. The combined effects of non-uniform specific charge and space-charge-limited conditions upon thrust, propellant flow rate, and payload ratio are studied, and a graphical investigation and interpretation is made.

This thesis will show that: (1) The existence of multiply ionized species in an ion beam will increase the space-charge-limited current over that expected in a beam composed of purely singly ionized ions, (2) the thrust produced by the ion beam is independent of the non-uniform specific charge distribution, …

An Automatic Data Acquisition System For Semiconductor Device Testing, Donald L. Bartling

Masters Theses

"An Automatic Data Acquisition System for determining the Voltage/Current characteristics of semiconductor devices is presented. The system is capable of measuring currents in the range from 10^-10 amperes to 200 milliamperes. The system includes various pieces of commercially available equipment plus several pieces of specially designed and fabricated equipment.

The system yields a maximum of 59 data points each for both the base and collector characteristics of the transistor tested. The system is designed to perform a particular sequence of events. These events are controlled by a specially designed and fabricated piece of equipment called the Control Center.

The …

Rc-Tunnel Diode Network Synthesis, Jerry Dale Lee

Masters Theses

"The synthesis of networks having prescribed transfer functions using resistors, capacitors, and one tunnel diode is presented.

The restrictions on the given transfer function are that it be a ratio of two polynomials in s, its poles lie on the finite, negative real axis of the s plane, and its numerator polynomial have only real coefficients, with a positive leading coefficient.

In general, this synthesis results in two two-port networks, each having a common connection between one input and one output terminal, connected either in parallel or series.

Procedures are presented for realizing any one of the several two-port network …

The Constant Impedance Tapered Lossless Transmission Line, Yu Kuo Chen

Masters Theses

"Considerable work has been done on the theory and development of the distributed RC network which is a special case of the general distributed network type of transmission line.

Sir William Thompson analyzed telegraph cables, assuming the RC line as a model. Oliver Heaviside made numerous contributions to transmission line theory. The solution of a two-wire transmission line with constant parameters R and C is obtainable by direct solution of the telegraphist's equations which are developed from the equivalent circuit of an incremental length of the network. The sinusoidal steady-state solutions of certain tapered RC lines have been exhibited. The …

An Investigation Of The Limitations Of The Antenna Range At The University Of Missouri At Rolla, Ronald Earl Nelson

Masters Theses

"The University of Missouri Antenna Range is described and criteria on range components for acceptable operation are discussed. Discussion of the results of an experimental investigation of component systems of the antenna range is presented. Experimental results are compared to criteria for acceptable operation and recommendations for the improvement of the facility is made. Suggestions are made as to its usage at higher frequencies"--Abstract, page ii.

Continuously Tapered Dielectric Matching Transitions For Waveguides, William E. Hord

Doctoral Dissertations

"Dielectric matching transitions at microwave frequencies are used for matching air filled waveguides into dielectric filled waveguides for maser work or into dielectric rod antennas. Also dielectric loading has been shown to improve the performance of the ferrite isolators.

The dielectric matching transitions that have been analyzed in the literature are of the stepped type. The continuously tapered dielectric matching transitions investigated in this dissertation provide increased bandwidth with very little increase of physical complexity.

The dissertation provides an analytical method for analysis and design for the continuously tapered dielectric matching transition. First-order and second-order approximate solutions for both symmetrical …

Galvanomagnetic Effects And Related Phenonmenon In Semiconductors And Dielectrics In A Radiation Environment, Leroy C. Meyer

Electrical and Computer Engineering ETDs

From Introduction:

In 1878, Hall found that the stream lines of an electric current in a metallic conductor were distorted when the conductor was placed in an external magnetic field. This distortion arises from an electric field set up at right angles to the current and to the magnetic field. The effect is well known in conductors and semiconductors, for both steady state and low frequencies Figure 1-1 illustrates the polarities of the Hall voltage for Ix in the direction of conventional current flow.

Optimum Linear And Adaptive Polynomial Smoothers, Stanley Bruce Alterman

Dissertations

The design of optimum polynomial digital data smoothers (filters) is considered for linear and adaptive processing systems. It is shown that a significant improvement in performance can be obtained by using linear smoothers that take into account known a priori constraints or distributions of the input signal. The procedure for designing optimum (minimum mean square error) adaptive polynomial data smoothers is then discussed and analyzed. The optimum smoother makes use of a priori signal statistics combined with an adaptive Bayesian weighting of a bank of conditionally optimum smoothers. Use of this technique permits large improvements in performance with a minimum …

The Rimo Filter, Richard Thomas Modafferi

Theses

Up to the present time, there has existed no general method for obtaining the pole locations of minimum-phase constant time delay filters of desired selectivity. Since constant time delay filters are necessary for low distortion FM transmission, and minimum-phase filters are easy to construct and align, a general method for locating the poles of minimum-phase constant time delay filters would be of considerable importance. Presented in this paper is a procedure for locating the poles of minimum-phase constant time delay filters of desired selectivity, using a FORTRAN digital computer program. Two experimental FM receivers were built to test. the new …

Determining And Telemetering Snowpack Water Content In Mountainous Terrain, Stephen Davis Clarke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Snowpack water content is an important parameter in streamflow forecasts. At the present time water content of the snowpack is determined by manual methods, which are often expensive and time-consuming. The use of a pressure pillow to determine water content has shown promise in experimental applications.

The design and analysis of a pressure transducer suitable for use with remote telemetry equipment is presented. The transducer uses changing fluid pressure to vary an inductor.

Telemetry techniques suitable for use on Utah snow courses are analyzed. Emphasis is given to the passive and active remote radio relays.

Iterative Method In Storage Routing, Mohan Lal Kapoor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study is to examine the feasibility of applying analog computer iterative methods to the study of storage routing.

Transient Response Of Linear Damped Lumped Spring-Mass Systems By Experimentally Derived Transfer Functions, Ralph W. Kelley

Electrical and Computer Engineering ETDs

In the field of mechanical shock testing, there are many instances where the responsive motions of linear undamped and lightly damped lumped spring-mass systems must be determined. If a model representing the system to be tested is available, it is possible to determine the responsive motion by several different approaches. Most of these methods require solving the differential equation of motion in some manner. Among the more common methods of solving the differential equation are the classical solution, the use of Laplace transforms, and various graphical techniques. All of these methods, however, require that a model of the system under …

Directional Effects Of Transient Radiation On Semiconductor Devices, Arthur C. Golubiewski

Electrical and Computer Engineering ETDs

The purpose of this study is to determine the directional effects of transient gamma radiation on electronic components. An analytic expression will be developed for radiation effect as a function of angle, and experiments will be described which verify the mathematical analysis.

The Electrical Conductivity Of Some Cryogenic Fluids, Walter L. Willis

Electrical and Computer Engineering ETDs

Cryogens (liquefied gases with low boiling points) are, in general, excellent insulators. Prior to this investigation, no measurements of conductivity in cryogens had been successful. An upper limit of conductivity in the range 10^-15 to 10^-17 mho/cm had been established for some cryogens. Data from the organic chemicals and petrol m industries indicated that fluids with conductivities in the 10^-11 to 10^-15 mho/cm range could present electrostatic potential hazards, particularly in situations of large volume storage and high flow rates. The advent of large capacity dewars and associated high flow rates of cryogens in the aerospace …

A Mechanical Thevenin Equivalent Circuit Of A Separately Excited D.C. Motor, Hershel R. Lung

Electrical and Computer Engineering ETDs

This problem is concerned with the transient analysis of a DC machine with constant field excitation. By using the generalized circuit concept and Thevenin's Theorem applied to this concept, the transient behavior of this type of machine can be found from an analysis of a lumped circuit model of the machine. The lumped circuit model is a three port device and as such, the terminal equations describing the relationship between the difference and flow signals at the various ports are nonlinear. The nonlinear terms due to the products of signals in the terminal equations can be eliminated by requiring that …

Small Prolate Spheroidal Antenna In A Dissipative Medium., William Troy Cowan

Electrical and Computer Engineering ETDs

A perfectly conducting prolate spheroidal antenna immersed in a conducting medium is analyzed. It is assumed that the dimensions of the spheroid are small compared to a skin depth in the medium. A gain factor for the antenna as a receiver is computed as a function of the spheroid's axis ratio. The prolate spheroid is assumed to be excited by a circular filament of magnetic current located in the plane of the spheroid's minor axes to approximate excitation by a magnetic toroid. Expressions for the antenna's input admittance and effective length are derived. Some experimental results verifying the derivation of …

Circular Polarization From A Corner Reflector Antenna With Tilted Dipole Of Arbitrary Length, Ruben A. Carrizo M.

Masters Theses

"The problem consists of the development of the electric far field equations for a forty-five degree corner reflector antenna with a tilted dipole, of arbitrary length, centered at the corner bisector plane to produce circularly-polarized radiation. The far field expression was developed as a function of the spherical coordinate system variables and placed in Fortran language in order to determine the dipole locations which would produce circularly-polarized radiation. At such dipole locations the field patterns were plotted in the [theta] = [pi]/2 and [phi] = 0.0 planes. Computations were made by the IBM 1620 digital computer"--Abstract, page ii.

On Time-Optimal Second Order Discrete Control Systems, Chao-Tai Li

Masters Theses

"The time optimal control problem in unforced discrete systems is studied in this thesis. Comparison is made between the discrete and the continuous control systems by means of minimum time isochrones. concerning optimal time, it is shown that using the discrete control system will take at most one more sampling period of time to go to equilibrium. An investigation is also made for the case when the time constant of the physical plant, G(s), and the control model are different. In such a case, an optimal trajectory can not be obtained. An adaptive process is proposed to adjust the model …

Matching Of A Horn Antenna To Its Dense Surrounding Media By The Use Of Artificial Dielectric Methods, Paul Arthur Ray

Masters Theses

"The purpose of this thesis is to design an artificial dielectric slug to match a horn in a media such as water and to discuss a method of determining experimentally its dielectric properties. The design is based on known artificial dielectric methods. The method of determining the dielectric properties is by microwave waveguide reflection techniques. This thesis deals with the theoretical aspects and suggests an experimental method of determining the practicability of such a matching method"--Abstract, page ii.

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.

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 …

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 …

A Circularly Polarized Corner Reflector Antenna, Walter Ronald Koenig

Masters Theses

"Image theory is used to develop the far field and polarization equations for a ninety degree corner reflector antenna. These equations are in terms of spherical coordinates, the length of the dipole element, the distance of the dipole from the corner of the reflector, and the angle of tilt of the dipole element with the apex of the corner. The equations are simplified to give the far fields in the vertical and horizontal planes for the special case of a half-wavelength dipole. An expression to calculate the distance of the dipole from the corner necessary to give circular polarization broadside …

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 …

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.

Analog Computer Study Of Unequally Spaced Antenna Arrays, Fred M. Dickey

Masters Theses

"The problem undertaken in this thesis was to study the basic properties of unequally spaced antenna arrays. The study was done on a trial and error basis by simulating the expression for the far field pattern of a general array on an analog computer. Many patterns were obtained from the analog computer for the purpose of comparison. The patterns of two spacing schemes that are typical of unequally spaced arrays are presented for the purpose of illustration"--Abstract, page ii.