Engineering Commons^™

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 …

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 …

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.

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.

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.

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.

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 …

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 …

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 …

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.

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 …

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 …

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.

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 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.

Production And Spectral Determination Of Low-Energy, Flash X Rays, Robert I. Loebman

Electrical and Computer Engineering ETDs

With the rapidly expanding use of X-radiation devices for medical, industrial and military purposes, the need arises for diverse methods of producing and measuring the X-ray portion of the electromagnetic spectrum.

X rays may be purposefully produced by a source in a continuous manner, in short pulses or flashes or in a random manner. X rays are also produced undesirably by devices having extremely high voltages or as a byproduct of some energy-producing device such as a nuclear weapon. In most cases X radiation is produced over a wide spectral range of varying intensities rather than at discrete energy levels …

Electronic Technique For Resolving Ambiguities Of Sinusoidal Function Transducers., James W. Campbell

Electrical and Computer Engineering ETDs

A circular function transducer is a device whose output is a circular trigonometric (sinusoidal) function of the input to the device. The sinusoidal nature of this class of transducer's output results in identical responses for many admissible inputs. Consequently, an ambiguity exists as to which of the many possible input values produce any particular output value. Even a history of the output from an initial reference input becomes ambiguous once the output completes one cycle of the sinusoid. To be a generally useful instrumentation component, the ambiguity of circular function transducers must be resolved.

Circular function transducers are currently used …

The Effect Of Nuclear Radiation On Oxidized Silicon Surfaces., Jerry A. Hood

Electrical and Computer Engineering ETDs

The change in properties of oxidized silicon surfaces with nuclear radiation is most apparent in devices controlled from the surface. The two devices of most specific interest are the insulated gate field-effect transistor and the metal-silicon dioxide-silicon capacitor. This chapter reviews the basic operating theory of these devices excluding the radiation induced defects. Many other devices such as the fieldister and surface-controlled avalanche devices would be equally or more sensitive than the two devices chosen for study. The devices chosen, however, are those of most immediate interest for use in a nuclear radiation environment .

An Analysis Of The Impedance Of Two Types Of Electric Antennas Designed For Undersea Applications., Vincent R. Chavez

Electrical and Computer Engineering ETDs

The problem of radio wave propagation using antennas submerged in sea water has received much attention in recent years. As early as 1940 Norgorden [1] prepared a paper on the problem of propagation of radio waves from a transmitting antenna in air to a receiving loop antenna in sea water. Further work on the loop antenna was performed in 1946 by Quinn and Norgorden [2]. An analysis of a Hertzian dipole in an infinite, conducting medium was done by Tai [3] in 1947. He showed that a meaningful expression for the radiation resistance of the Hertzian dipole in a conducting …

An Analysis Of The Signal Processing In A Radio Altimeter Utilizing Random Angle Modulation, Donald F. Post

Electrical and Computer Engineering ETDs

Excerpt from the introduction:

This paper presents an analysis of the signal processing in a continuous wave, fixed-range, radio altimeter which utilizes random angle modulation, i.e., the modulating function is a sample function from a random process. The mathematical model of the altimeter is shown in block diagram form in Figure 1, and the physical situation in which the altimeter operates is illustrated in Figure 2. As shown in Figure 2, the altimeter is assumed to be on the vehicle "V" which has a relative velocity v with respect to the reflecting plane P. The velocity vector might have any …

A Study Of Learning In Adaptive Systems., In Ku Kang

Electrical and Computer Engineering ETDs

The purpose of this study is to investigate the structures of learning processes and their applications to adaptive systems. The learning processes in this study are based on Bayes learning model, which well describes the nature of learning and also is a natural choice from the viewpoint of statistical decision theory.

On The Application Of Bayesian Learning In Discrete Communication Systems., Chien Fong Chao

Electrical and Computer Engineering ETDs

It is the requirement of many communication systems that the transmission of information should not only be reliable, but also efficient with respect to the capacity of the communi­cation channel used.

Improving The Reliability Of Electronic Systems By Minimization Of The Variances And Stabilization Of The Mean Values Of The System Performance Criteria, Emil Carl Neu

Dissertations

The parameters of an electronic system are not deterministic variables; but rather because of variations in manufacturing processes, they are randomly distributed variables. In addition, aging mechanisms will cause these parameters to drift with time. As a result of both of these factors, the system performance criteria deviate from their initial design center values. This research studied the effect of component parameter variations upon these electronic system performance criteria and then presented a thesis to minimize the effect of these variations.

The distributions of the performance criteria were obtained as functions of the parameter distributions, by first approximating the performance …

Design Of Feedback Control Systems With Transport Lag By Parameter Plane Techniques, Lawrence Eisenberg

Dissertations

A method is presented for the exact determination of absolute and relative stability of linear feedback control systems containing transport or distributed lag. All results are in terms of two variable system parameters. The method utilizes an extension of modern parameter plane techniques that allows for the inclusion of transcendental functions in the system characteristic equation. The design of controllers in linear systems containing transport lag is then considered. A design technique is proposed that allows for the systematic determination of two variable controller parameters in order to meet frequency or time domain design specifications.

The design technique is formulated …

Transient Radiation Effect On Semiconductor Controlled Rectifiers, Wilford D. Raburn

Electrical and Computer Engineering ETDs

Excerpt from the Introduction:

The three terminal PNPN switch which we will refer to as the semiconductor controlled rectifier or SCR has electrical characteristics quite similar to the gas thyratron [7]. In the SCR, current is carried by electrons and holes whereas, in the thyratron, it is carried by electrons and ions. Both have high impedance in the "off" state and low impedance in the "on" state. Both devices will remain in the conducting mode once they have been triggered, even if the gate signal is removed.

The operation of the SCR depends upon the internal feedback mechanism [ 22]. …

A General Approach To The Analysis Of Particle Transport In Solids--With Particular Application To High Frequency Effects On Charge Transport In Semiconductor Devices, Raymond A. Gore

Electrical and Computer Engineering ETDs

The purpose of this first chapter is to review the basis of the diffusion theory description of particle motion in solid material and its application in the analysis of semiconductor devices. Diffusion theory, as used throughout this dissertation, will be used to mean the special case of the more rigorous transport theory that results from assuming an infinite particle velocity and a constant ratio of particle velocity to the probability of a collision. Thus, the discussion of diffusion theory begins with transport theory, and in particular with the Boltzmann transport equation. Therefore, this chapter begins with a formulation of the …

The Effect Of Potential Representation On The Electron Scattering At Low Energies., Ahmed K. Aboul-Seoud

Electrical and Computer Engineering ETDs

One of the most useful approaches for gaining understanding of atomic structure is that of experiments involving electron scattering from atoms. In particular, knowledgle of differential and total elastic scattering cross sections enables one to calculate momentum transfer cross sections, mean free path, and the width of multiple scattering distributions. From the point of view of a theorist, the central question is that of the interaction potential. A representation of this latter quantity will give rise, mathematically, to a two point boundary value problem involving the Schrödinger equation. Upon solving the Schrodinger equation, and satisfying the appropriate boundary con­ditions, the …