Digital Commons Network^™

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 …

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.

Reviews Of Books And Papers In The Computer Field, James H. Tracey

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Analysis Of The N-Wire Exponential Line, Edward C. Bertnolli

Electrical and Computer Engineering Faculty Research & Creative Works

A new approach to distributed network analysis is presented with the analysis of the n-wire exponential line as example. This approach provides the distributed network's transfer matrix in a form useful for both transient and steady-state network calculations. © 1967, IEEE. All rights reserved.

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 …

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.

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 …

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 …

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.

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 …

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.

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 …

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 …

Determining The Best Computational Method For Simulation, Neil Hertenstein

Masters Theses

"Two related problems are treated in the discussion. First, what is the best computational means to be used to simulate a given system? Second, if hybrid is chosen, how do we assign the problem to the different computers to realize the fullest advantage of the hybrid simulation? Most of the available information in the literature is presented in light of the above questions. It is found that, despite the lack of a precise theoretical solution, much insight can be gained into the problem. A proposed procedure for hybrid assignment and a sample problem using this procedure completes the discussion"--Abstract, page …

Analysis Of Time-Varying Linear Multipole Filters With Sampled Nonstationary Random Inputs, Ming-Chwan Chow

Masters Theses

"In this thesis an analytical method is developed to determine an optimum time-varying linear filter in order to satisfy the following specifications. The filters are of sampled data multipole form with n inputs and m outputs. The signal of each input is a member of a nonstationary random process, and the signal is corrupted by stationary noise.

The statistical optimization theory developed by Wiener is extended to a linear time- varying filter with nonstationary input. Correlation functions are defined for nonstationary ensembles. The mean- square error is calculated in terms of these correlation functions. By minimization of the mean-square error, …

A Nonlinear Sampled Data Feedback Control System Employing Pulsed Thrust Position Control, John D. Corrigan

Masters Theses

"This thesis shows that reaction jet thrust pulses, each of constant amplitude and time duration, in conjunction with sampled data error information can provide satisfactory position and/or attitude control for space vehicles.

Incremental phase-plane analysis of the system yields a technique for determining system response and suggests a means of compensation. Control system response for the vehicle under the influence of external forces is shown to be satisfactory by digital computer simulation"--Abstract, page ii.

Analog Simulation Of The Voigt Solid, Richard F. Pohl

Masters Theses

"A method of reducing a mixed partial differential equation with boundary conditions to a form suitable for programming on the analog computer is developed. Presented along with the computer program set up to be used on the EAI TR-48 analog computer is a systematic check procedure to indicate possible computer malfunctions and programming errors. The results of the computer simulation are presented and supported with observed data"--Abstract, page ii.

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 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 …

Space-Charge Effects As Determined By Initial-Field Conditions, Tsing-Yih Wang

Masters Theses

"A method for calculating the current density passing between two parallel plane electrodes for different values of positive charges as a function of " field at the emitter to field for no charge ratio " is presented.
The problem of the potential distribution between the electrodes has been solved for one particular case in which the positive charges are assumed to be proportional to the field at the emitter. The expressions for the electric field, the velocity of charges, and the charge density as a function of the potential are also presented and plotted as a function of the distance. …

An Application Of The Variable Gradient Method Of Generating Liapunov Functions To Discrete Systems, Henry N. Peterson

Masters Theses

"The variable gradient method of generating Liapunov functions has been used only for continuous systems. This thesis presents an application of the variable gradient method to non-linear sampled data control systems.
Certain modifications to the variable gradient method are developed and several examples are presented which demonstrate the application. An attempt was made to synthesize the control system parameters, but due to the complexity of the ΔV functions, the synthesis in general cannot easily be obtained . To circumvent the problem of determining if the ΔV functions are negative definite, a set of computer programs were written to determine a …

A Periodic Dielectric Rod Antenna, Robert C. Peirson

Masters Theses

"The periodic dielectric rod antenna structure under consideration consists of identical dielectric rod sections of radius a meters situated on a common axis. These sections are of length 1₁ meters and are separated in free space by distance 1₂ meters.

Field analysis employing Floquet's theorem, in terms of the exemplary TM₀₁ circular mode, gives expressions for the various field components and an eigenvalue equation. Digital solution of this eigenvalue equation establishes the location of propagation bands as a function of frequency. Such bands are characteristic of any periodic wave guiding structure."--Abstract, page ii.

An Algorithm For The Synthesis Of Nand Logic Networks Using A Diagrammatic Approach, Donald Robert Nelson

Masters Theses

"A diagrammatic approach is presented for the synthesis of multilevel NAND networks realizing combinational logic expressions. The network synthesized is restricted to only uncomplemented inputs. The synthesis algorithm involves the determination of minimum sum of products and product of sums expressions for a Boolean function, construction of an α-ß diagram from these expressions followed by implementation with NAND gates directly from the diagram. The resulting network is a minimal or near minimal NAND gate realization of the given function. The algorithm is applicable to completely or incompletely specified Boolean functions and is extended to include NOR synthesis"--Abstract, page 2.

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.

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 …

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.

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.

A Computer Approach To Transistor Circuit Design, Kwok Chee Hong

Masters Theses

"The design of amplifiers is usually approached through experimental study. This thesis proposes a mathematical approach, using a digital computer to predict the performance of an active transistor circuit (a frequency equalizer circuit to compensate for the RIAA recording frequency characteristics) prior to the actual construction of the physical system. The simple but powerful computer analysis method will be based upon the nodal equations of the complete circuit. The primary aim is to design a circuit which would give a desired frequency-gain characteristic. The complete set of simultaneous complex nodal equations describing the circuit operation is then written. Based on …

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 …