Engineering Commons^™

A Method For The Calculation Of The Electric Microfield Distribution In A System Of Charged Hard Spheres, Ronald M. Flegal

Masters Theses

No abstract provided.

The Development And Use Of A Double Beam Photoelectric Polarimeter For The Study Of The Faraday Effect, John Norman Rowe

Masters Theses

No abstract provided.

Negative Resistance In Cadmium Sulfide., John William Mohr

Masters Theses

"A light-sensitive, negative-resistance phenomenon has been observed in a special two-terminal CdS device fabricated from selected single crystals. The device differs from those used in previous investigations in that one end of the device was masked to keep out visible light and that the phenomenon was observed at room temperature. A method is described which enables the phenomenon to be observed on a reproducible basis. It was found that the CdS single crystal must have a relatively high density of traps. Possible mechanisms which may contribute to the phenomenon are discussed"--Abstract, page ii.

Digital Filter Design And Evaluation, David Alvarado MaguiñA

Masters Theses

"This thesis is concerned with the application of two digital filter design techniques to the Pade approximate continuous filters. The (m, n) Pade approximant has a numerator polynomial of degree n in s and a denominator of degree n in s. The (n-1, n) approximates are desirable for linear phase low pass filters, pulse delay circuits without initial condition errors, and pulse forming networks. A collection of plots is shown to demonstrate the quality of the approximations in the frequency domain, as far as amplitude and phase are concerned. These low pass approximants are normalized to a cut-off frequency of …

Design Of A Nonparametric Detector For Fm Signals, James Charles Fowler

Masters Theses

"The communication engineer has in the past treated the detection problem from a parametric point of view. That is, the signal has been assumed to be of a known deterministic form and the noise of a known statistical form. This approach has proved valuable in many cases, but it is subject to severe limitations, e.g., if either the noise or signal change form, a new detector must be designed. Because of these limitations there is a need to find a more general form of detector.

This study looks at a specific statistic (the Cramér-von Mises statistic) and designs a detector …

The Design Of A Drum Memory System, Frederick W. Lynch

Masters Theses

"Three methods for obtaining an auxiliary memory for an SCC-650 (Scientific Control Corporation) digital computer are presented. A logic design is then developed on the basis of using the drum and write circuits from an available IBM-650 digital computer and constructing the remaining logic functions. The results of the logic design are the transfer equations necessary to implement the memory system"--Abstract, page ii.

Mode Analysis Of The Unsymmetrically Fed Ground-Plane Aperture, John G. Hemmann

Masters Theses

"The problem of radiation from a waveguide-fed ground-plane aperture perturbed with a wedge-shaped dielectric insert was examined more carefully. The work initiated by Blumberg was continued, using a greater range of dielectric constants and smaller increments of angle.

Aperture field measurements were made over a range of dielectric constants for each wedge angle, in order to determine the change in amplitude distribution as a function of permittivity. Aperture phase measurements were also taken for selected angles. These were used with the amplitude data to predict, using numerical integration, the far-field radiation patterns of the perturbed aperture. Far-field patterns were then …

Determining The Transfer Matrices Of Tapered Multiwire Transmission Lines, Clyde A. Vandivort

Masters Theses

"The advent of monolithic and integrated microelectronic circuits has aroused interest in passive multilayered thin film networks. The basic thin film network is shown in Figure 1. This structure consists of alternate resistive and dielectric layers sandwiched together. Such devices are referred to as distributed parameter RC networks. The reduction of volume and increased reliability offered by thin film devices has caused considerable effort to be extended in the analysis of their characteristics....

The incremental equivalent circuit given in Figure 2 stems directly from the above physical parameters and is the circuit used as a basis for the analysis that …

A Multiple-Input Chemical 'Memistor' For Adaptive Circuits, Richard Franklin Crall

Masters Theses

"A modification of Widrow’s "memistor" is made in a form suitable for extension to multiple-input devices. This modified form is extensively investigated using analog field maps, and through experimental testing. The multiple-input device presented exhibits good adaptive characteristics and reduces the number of interconnections required in the external circuitry"--Abstract, page ii.

A Study Of Probability Of Error Calculations For Baseband Multi-Level Digital Transmission Systems Using The Fixed Threshold Decision Rule, Don J. Popp

Masters Theses

"This study is an investigation into analytical techniques used in deriving probability of error expressions for baseband multi-level digital transmission systems. A fixed-level decision rule is used to solve this statistical detection problem together with some simple concepts from probability theory. To illustrate these techniques, probability of error expressions are derived for the general uncoded system, a simple coded system, and a complex coded system. Curves of probability of error versus signal-to-noise ratio are plotted for the various systems considered"--Abstract, page ii.

The Realization And Application Of Parallel Linear Feedback Shift Registers, Ross K. Heitzmann

Masters Theses

"Two methods for serial-to-parallel transformation of linear feedback shift registers are briefly discussed. A third method for transformation is rigorously developed using a next-state and output equation representation of the linear feedback shift register. An algorithm is developed for simplifying the parallel machine resulting from serial-to-parallel transformation, where simplification is defined as reduction in the required number of modulo 2 adders. A computer program incorporating serial-to-parallel transformation and the simplification algorithm is provided "--Abstract, page ii.

Minimization And Generation Of Next-State Expressions For Asynchronous Sequential Circuits, Gary Keith Maki

Masters Theses

"One step in the synthesis procedure for realizing an asynchronous sequential circuit that is operating in fundamental mode is to obtain an internal-state assignment that will realize the operations of the circuit. Often the procedures that are used in accomplishing the above task generate several satisfactory assignments. The first part of this paper presents a method that will enable one to predict which of the internal-state assignments will yield a simpler set of next-state expressions. A second topic treated in this paper is one of presenting a method to generate the next-state expressions for an asynchronous sequential circuit directly from …

Small-Signal Impedance Of A Junction Diode At High Injection Levels, John E. Lundy

Masters Theses

"A mathematical expression for the driving point impedance of a junction diode at high injection levels is developed. To evaluate the impedance versus frequency characteristic of a diode, it is necessary to know the minority carrier lifetime as a function of injection level and doping density in the base (lightly doped) region, the junction area, and the base width. The interesting characteristic of the diode impedance at high injection levels is the inductive reactance displayed by the diode.

The expression is developed by solving the differential equation for charge flow in the base region of a diode assuming space-charge neutrality …

A Class Of Pattern Recognition Machines, Shaw Yih Chung

Masters Theses

"The classification of signals through the use of pattern recognition techniques may be viewed as a statistical classification problem since at least some pattern classes are analog signals which have been contaminated by additive noise. In order to represent these signals at the input of a pattern classifier they are sampled and a vector and an m-dimensional vector space used to describe the pattern. Consequently, these pattern samples are processed to determine the parameters of the statistics. In this study the additive noise was assumed to be Gaussian in nature. This study was based on a priori knowledge of the …

A New Performance Index For Sensitivity And Energy Optimization., Mohamed Zafer Dajani

Masters Theses

"The principal aim of this thesis is to present a new index of performance which when minimized will simultaneously optimize the system energy and sensitivity function of a multivariable linear control system. With this performance index it is usually desirable to discriminate between the sensitivity factor and the energy term by weighting them differently. Two types of weighting factors are presented. Since it is not easy to minimize that performance index for all types of problems, further research is suggested to find methods of solution for such problems. Illustrative examples demonstrate the optimization process and the type of assumptions needed …

Fault Detection In Combinational Networks, Alexander Rahm

Masters Theses

"This paper presents an algorithm for locating a failure in combinational logic networks, which is a problem of importance in the maintenance of computer systems. The procedure is based on the "path sensitizing" idea for fault detection. The networks considered are non-redundant, consisting of AND, OR, and NOT elements. The class of faults investigated is that which causes a connection to appear to be logically suck-at-one or stuck-at-zero, and only single failures are treated. It is shown that the failure is generally located to a specific "fault group"--Abstract, page 2.

Scanning Properties Of Unsymmetrically Loaded Aperture Arrays, Gary Dean Brunner

Masters Theses

"Radiation patterns resulting from an array of waveguide-fed apertures, filled with assymmetrically [sic] cut dielectric inserts, in an infinite ground plane were investigated. The results of Blumberg and Hemmen concerning single apertures were applied to a two-aperture array, with emphasis upon obtaining an array capable of scanning in the far field through changes in the permittivity of the assymmetrically [sic] cut dielectric inserts. Scanning was shown to be possible with up to a 60⁰ scan angle with a "push-pull" method of varying permittivities, in which the permittivity of one insert is raised while the other is lowered. The aperture field …

Annealing Characteristics Of Neutron Irradiated Silicon Transistors, Joseph Robert Chott

Masters Theses

"When a transistor is subjected to neutron irradiation, a component of base current proportional to neutron fluence is induced. From the effects of annealing on the base and collector currents, the conclusion was drawn that there is an apparent difference in the annealing characteristics between the neutral and the space-charge regions of the semiconductor device. This study of the anomalous annealing indicates that the neutron-induced component of base current is a result of one, or a combination, of the following mechanisms: a quasi-tunneling recombination phenomena in the emitter-base space-charge region, or an influence of the p-n junction electric field on …

Characteristic Impedance Of Open Microstrip Transmission Lines Having Finite Thickness And Multiple Dielectric, Philip Julian Carter

Masters Theses

"A computer program is provided for determining the characteristic impedance of microstrip transmission lines having finite thickness. Infinite and finite ground planes are incorporated into the program. The programmer need only supply information in the form of a data card. This procedure is clearly outlined.

Graphical solutions of characteristic impedance for multiple dielectric microstrip transmission line problems are obtained using a discrete resistive analogue. Computer network analysis programs are viewed as having several advantages not possessed by the physical resistive analogue"--Abstract, page 2.

A Programmed Synthesis Procedure For Asynchronous Sequential Circuits, Robert Judson Smith

Masters Theses

"The synthesis procedure for large asynchronous normal fundamental-mode sequential circuits is time-consuming and tedious when performed manually. This paper describes a series of computer programs which, given a machine specification in flow table form, automatically produces simplified normal form implementation design equations. The user may specify that either minimum-variable state assignments, or more rapidly generated near-minimum-variable codes be found. Next-state equations are formed using the generated state assignments and converted to simplified sums of products. Sample machines having flow tables of up to eighteen rows by four columns are synthesized"--Abstract, page ii.

Construction Of A Laboratory Type, Convertible Excitation Argon Laser, Arthur P. Reckinger

Masters Theses

"The purpose of this thesis is to describe the construction of a general purpose, convertable [sic] excitation, laboratory type, argon laser. Quartz tubing was used in the final model while attempts to use alumina were made during earlier work. The final model has total optical power output of 230 mw at a discharge current of 29 amperes in the dc excitation mode. Provision was also made to utilize RF or pulsed excitation. The device is built so that several values of optical transmittance are available with a wide range of mirror placement"--Abstract, page ii.

Programmed State Assignment Algorithms For Asynchronous Sequential Machines., Wayne L. Schoeffel

Masters Theses

"An important step in the synthesis procedure for realizing a normal fundamental mode asynchronous sequential circuit is the internal state assignment. Although systematic methods have been developed to construct minimum-transition-time state assignments, they become long and tedious with hand methods for machines with more than 7 or 8 internal states. To extend the application of these algorithms to larger problems, this paper presents an efficient digital computer program for generating minimum-variable state assignments. An alternate program is also presented which, though shorter, does not guarantee a minimum-variable assignment"--Abstract, page ii.

Synthesis Of Filters Using Distributed Rc Networks, Mario Nader Nader

Masters Theses

"This paper deals with the problem of realizing filter and delay functions by means of distributed RC devices. The method is made possible through the use of a distributed RC network which possesses rational admittance parameters. The technique of approximating transfer functions using polynomial factors that are ration in e[superscript (a square root of s] is explained. These factors are used to approximate the magnitude and phase characteristics for a low-pass filter. This filter is then realized using the admittance functions studied by Wyndrum, the "s->W" transformation, and Richard's theorem. Those factors are then used to approximate high-pass and …

A Shunt-Feed Antenna System On A Small Supersonic Aircraft, Larry Joseph Nanney

Masters Theses

"A technique was developed which successfully predicted the reactance of a shunt cavity exciting the air frame of a small supersonic aircraft as an antenna. This was possible by the use of the wire above a ground place approximation which closely defined the characteristic impedance of the shunt fed cavity. A correlation was made between the maximum values of parallel resistance of the shunt fed cavity and the length of the air frame or portions of the air frame, which at this point were found to be a quarter wavelength in length. Measurements of the impedance of the shunt-feed system …