The feasibility of utilizing acoustic imaging techniques for
improving the undersea viewing capability of small submersibles is
investigated. The limiting values of major parameters in acoustic
imaging systems are established and graphs which illustrate the
parametric relationships are presented. A series of sample calculations
illustrate how the graphs can be...
The purpose of the thesis is to design, construct,
program, and test an automatic integrated circuit test
system. The class of integrated circuits tested was restricted
to digital integrated circuits. The general concept
of testing a digital integrated circuit is based on
the truth table of that circuit. A combination...
The feasibility of using the Franz-Keldysh effect in practical
light intensity controlling devices was investigated.
Reverse-biased diodes made from CdS were implemented to obtain
high electric fields necessary for the effect. The three types of
diodes studies were: MIS, metal-semiconductor barrier, and p⁺-n
heterojunction. An expression for the change in...
This thesis develops a simplified and logical simulation model
for an amplidyne excitation system for a synchronous generator with
an automatic voltage regulator.
The non-transfer function representation using field determined
parameters including variable inductance and machine saturation
was used to reduce the computing time for the stability analysis.
The simulation...
A non-volatile electrically alterable read-only memory using
an MOS field effect transistor with a threshold voltage which depended
upon the position of ionic charges for its memory was fabricated.
The conventional silicon dioxide layer was replaced by a composite
layer consisting of thermal silicon dioxide, electron beam
evaporated aluminum oxide,...
A new, computer oriented system for automatic, in situ
monitoring of water quality is proposed which makes full and effective
use of modern computer technology. The main objective of this thesis
work was the development of the concept for in situ computer controlled
experimenting as a reasonable and effective means...
The power spectral density of the acoustic signature of
Dungeness crab was calculated by the use of digital computer.
The signal produced by the Dungeness crab was an analog signal.
Therefore a conversion of the signal from analog to digital was
necessary. This was done by sampling the acoustic signature...
The purpose of this thesis is to investigate the necessity of
transposition in the construction of overhead transmission lines.
Line currents, line voltages and line losses of both the transposed
and untransposed lines were calculated and compared for two different
voltage classes. The conventional method of symmetrical components
was used...
The purpose of this study is to investigate radiation
losses in microstrip circuits. Expressions are derived to
evaluate the radiation resistances (or conductances) for
single terminated, open and short-circuited lines. The
quality factor Q of open and short-circuited stubs is
evaluated. An analytical procedure is formulated to
evaluate the radiation...
A simulation method using a hybrid computer is developed in
this dissertation to enhance the study of wind-driven ocean circulation.
The simulation is based on the mathematical model developed by
Ekman. Pure digital simulation is not economical due to excessive
computer time required for the solution of the partial differential...
Most technological problems associated with man-machine conversations
have been solved and are well documented in both the
contemporary technical and lay literature. The major remaining
technological problem is the real time conversion of a human's vocal
uterances into a "written" phoneme sequence representing the information
content of speech. The work...
It is popular belief that the volatility of the exchange rate is due
to the balance of payments, which in turn is mainly influenced by the
balance of trade. A closed-loop dynamic economic model is proposed
to describe and analyse the effect of the international trade of a
country on...
This paper investigates the benefit of various parallel processing
architectures for a Command and Control system for the Royal
Thai Air Force. Parallel processing has been shown to be useful
for air defense and air traffic control applications. Its advantages
are examined within the constraint imposed by the available
resources...
The exponentially tapered, nonuniform transmission'
line, applied as an impedance transformer, is analyzed and
modified. The analysis develops an expression for the input
reflection coefficient that has the magnitude and phase
as distinct functions. This allows ease in comparing the
approximate and exact solutions and in developing the S-parameters for...
Recent acheivements in high speed digital integrated
circuits has prompted the system designers to search for
a practical method of inter-connecting these high speed
circuits. This paper describes the implementation of the
microstrip transmission line on a high speed digital
data bus. Transmission line and characteristic impedance,
termination with single...
The dynamics of land use in the State of Oregon are simulated
on a digital computer. The introductory chapter outlines the complex
nature of the problems facing the post-industrial society and argues
that the scientific and professional estates share in the responsibility
for public policy formulation. The second chapter .presents...
This paper is concerned with the application of
hierarchial and parallel computing structures to digital
data communications processing in a multi-access telecommunications
environment. Designs are analyzed and
evaluated in terms of data collected from remote access
tele-communications traffic and in terms of the application
to several processing problems in the...
A liquid crystal thermographic technique was developed
for application to several problems in clinical
medicine and physiology. The procedure was inexpensive,
rapid, simple, versatile and acceptable to patients.
Investigators in the past have used cholesteric liquid
crystals for thermography but their use was limited to
research in the medical field...
REGTRAN (REGister TRANsfer), a hardware description
language and SYSSIM (SYStems SIMulation), a simulator for the
system described by REGTRAN were originally developed by Edward
Pett, Jr [33] at the University of Texas at Austin. These two programs
are successfully used to simulate many digital systems of
complex nature. It is...
The question of the suitability of Walsh functions or
similar bi-valued functions used as a radar electromagnetic
carrier waveform is considered. Walsh functions are
described and effective sinusoidal steady state transfer
functions are defined for transmission elements, antenna
systems, and propagation media.
The argument is made that the unit impulse...
This report is concerned with the analysis of the effect of
finite wordlength, channel capacity and source rate in digital feedback
control of linear systems. The cases considered are (1) finite
wordlength A/D conversion, no feedback delay, ideal ROM (read
only memory) controller; (2) finite A/D wordlength (source rate),
state...
The objective of this thesis is to develop criteria for a data
acquisition system for electrical machinery capable of sampling a
signal every 0.2 msec with a desired accuracy of 0.1%. The system to
be measured includes both AC and DC voltage and current signals from
several points. The main...
CP1100/GPIB Interface is an interface between the "General
Purpose Interface Bus", which is an implementation of the Universal
Bus described in IEEE Standard 488-1975, and Unibus. This interface
enables TEKTRONIX CP1100 series controllers to operate
GPIB- compatible instruments connected to the General Purpose
Interface Bus. The designer can now incorporate...
In an attempt to provide a practical means to measure the information
processing capacity of a real-time digital processing system a
theoretical framework, the Real-Time Schemata, whose basis is a
schematic description and a measure of "useful information," is presented.
The description applies to processes that would typically be
implemented...
The purpose of this thesis is to represent and calculate unsymmetrical
secondary faults on a grounded wye-to-delta transformer
bank.
This thesis is specifically concerned with the secondary connections
often encountered in industrial installations. Faults on these
systems have not been adequately investigated.
Three types of faults are considered, namely:
1....
A procedure for displaying cursory computer analyses of time
series acoustic signals is described. The graphic presentation is
optimized for visual analysis. The results displayed represent time
series signals and/or Power Spectral Density estimates.
Both hardware and software components of the procedure are
described and compared with current methods. Suggestions...
A model of a squirrel cage induction machine, d.c.-
link power supply and centrifugal pump is developed and
used in the design and evaluation of a perturbation feedback
control system for a sewage pumping station. A comparison
of the simulation model of the induction machine
and a laboratory machine to...
It has been established that bilinear models
occur frequently in nature and offer some important
advantages from the standpoint. of controllability,
optimization and modeling. The estimation of
bilinear systeim models from the Measurements
of input-output data are discussed. In the
first approach a parametric model of a discrete-time
linear system...
Bilinear systems due to their variable structure properties
offer more versatility in modelling of nonlinear processes than
linear systems.
The state estimation problem for a continuous bilinear system
with a continuous observation model is studied and the results are
extended to the case where the observations are of a discrete...
A compartmental model of the immune system is simulated.
Chapter I discusses the importance of such a
model, reviews past immune system models, and summaries
the immunological theory the model is based upon. In
Chapter II, the compartmental representation of the immune
system is developed from immunological and physiological
theory....
In this dissertation, a new computational method for equality constrained nonlinear programming is developed. Specifically, problems of minimizing a nonlinear objective function f(x) subject to constraints h(x) = 0, where f is a scalar valued, x is an n-vector and h is a m-vector with m < n is considered....
This fault detection scheme is based on sampling the instantaneous
phase voltages and checking their sum and magnitude against
a specified voltage. Faults on the system cause unbalances and
distortion of the phase voltages and currents. The currents and
voltages change in magnitude and/or phase position with respect to
the...
A new modular loop architecture for distributed computer
systems has been developed and compared with three of the most
prominent loop architectures currently being used. The competitive
loops with which the new architecture has been compared
are the Newhall loop, the Pierce loop and the DLCN loop. The four
loop...
The effect of the mutual inductances between the rotor coils of a synchronous machine on its defined reactances and predicted transients are investigated. Two linearized models of the machine are considered. One uses the Laplace-Transform approach, with minimum number of assumptions on the inter-coil couplings, in developing a model for...
Bilinear systems, encountered in many important applications of engineering, biological and socio-economic systems, represent the logical step in complexity between the linear systems which are inadequate in the modeling of various dynamic processes and the difficult realm of nonlinear systems. This dissertation studies two functional expansions in bilinear system analysis-...
Decimation and interpolation is shown to be an effective technique
for reducing the storage requirements for bandlimited time series.
Interpolation and decimation is theoretically developed using z-transform
theory and graphically interperted. A sequence of data acquired by sampling
a sonar signal is used to demonstrate the effects of decimation. Using...
With the advent of LSI, iterative forms of realization
of digital systems are becoming increasingly popular with
system designers. Many problems occurring in digital computer
design render themselves suitable for iterative
realization. These include adders, arithmetic logic units,
coding and decoding circuits and so on. Fault-free functioning
of such systems...
As a significant class of nonlinear systems, bilinear systems (BLS) are extensively developed in the past years. In addition to their advantages over linear systems which are often not adequate to represent accurately many control processes, the BLS are particularly appealing in modeling biological systems in which parametric controls are...
The purpose of this research is to develop methods to
translate a certain machine independent intermediate
language (IML) to efficient horizontal microprograms for a
class of microprogrammable machines. This IML has been
developed by Malik (12) and is compiled directly from a
high level microprogramming language used to implement a...
This thesis presents work done to verify the accuracy of a
heuristic method for computing availability percentiles for
cascaded independent systems. Previous work has provided a model
for a single line that will be used as the basis for a simulation
of cascaded and parallel systems of lines. The simulation...
A variational integral method in the Fourier transform domain is
used to calculate the characteristic normal mode parameters of a coupled
pair of nonsymmetrical microstrip transmission lines in an inhomogenous
dielectric medium under quasi-TEM conditions. These together with the
theory of such structures are used to show that ideal directional...
The purpose of this research is to design a high level language
(HLL) suitable for microprogramming. A top down design technique has
been adopted which makes the language design process simple and
accurate.
The primitive operations of a high level language for producing
emulators is shown to include special purpose...
An important step in the design of digital networks lies in the derivation of the switching formulas which describe the combinational logic networks in the system. In most large systems the number of gates and the number of connections are major factors that affect the cost of the system. An...
An advanced forward 'area tactical radar network, now under
conceptual development by the Air Force Electronic Systems Division,
can be viewed as a novel form of computer network but with
other unique problems resulting from the specialized nature of the
application. The proposed network will link together a number of...
The order of the practical system (e.g. nuclear power
plants, electrical power network and chemical plant) is
quite large. However, there are many limitations in computing
facilities for the large system. Because of these
limitations, it is often necessary to reduce the order of
the large system using an approximation....
The suitability of discrete least-squares optimal (Wiener) filters
for deconvolution of tone-burst waveforms is studied. It is shown
that: (1) such waveforms are not well suited to these filters without
preprocessing, (2) the use of exponential weighting results in a significant
improvement in filter performance and (3) that "phase-unwrapping"
in...