Engineering Commons^™

Statistical Analysis Of Critical Flashover Voltage And Standard Deviation Of Switching Surges And Lightning Impulses, Gurdip Singh

Masters Theses

"In order to analyze critical flashover voltage methods a set of experimentally determined data has been used. This data was supplied by the A. B. Chance Company. The data presents the flashover probability as regards to impulse voltage. The various correction factors have been applied to get the corrected impulse voltage, thus eliminating the effect of atmospheric conditions such as temperature, pressure, and humidity. The experimental observations have been analyzed by the application and use of the method of moments, regression analysis, graphical analysis with iterative techniques and maximum likelihood method. From the results, it was found that the maximum …

A Formal Description Of The Nova-800 Computer In Computer Design Language, Ronald Lee Engelbrecht

Masters Theses

"This paper presents a formal description of the operation of the NOVA 800 in Computer Design Language (CDL). For simplicity, the description does not include specific input/output devices, the multiply/divide option, or data channel operations. The description is intended to be used as a supplement in a basic course in computer organization, and an example of its use is included"--Abstract, page ii.

A Study Of The Measurement Of Noise Power, Larry Smith Heflin

Masters Theses

"In order to compute a power signal-to-noise ratio in the numerical simulation of a communication system, it is necessary to measure the power of the noise present. The required integration can be approximated by many numerical techniques. Five numerical integration methods are available in the user-oriented System/360 Continuous System Modeling Program. Measurements of the power of an additive Gaussian noise waveform are performed, and an analysis of the accuracy of the measurement compared to theoretical values is presented"--Abstract, page ii.

Ideal Filter Approximation And Synthesis, Patrick Shu Yau Ho

Masters Theses

"Several methods are currently used for approximating the ideal low pass filter. Generally, those approximations relate only to the amplitude or phase characteristic of the ideal filter. A class of filters has been proposed as approximating both the amplitude and phase characteristics of the ideal filter. The characteristics of the first ten members of the proposed class are considered in this paper. The results indicate a much improved approximation to the ideal filter has been achieved"--Abstract, page ii.

Power, Divergence, And Stability Factors Affecting The Use Of A Krypton Laser As A Multispectral Illumination Source, David Perry Owsley

Masters Theses

"Specific performance characteristics of a krypton laser were measured. Evaluation criteria were dictated by the proposed use of the laser as a multi-wavelength illumination source. The laser output power, spectral power distribution, and output stability were measured as a function of wavelength and transverse mode order, to determine optimal operation characteristics. Data are presented defining the compromise between laser output power and beam divergence when the laser is operated multi-wavelength, and in several low-order transverse modes. There is an advantage of increased output power when the laser is operated in transverse modes higher in order than TEM₀₀, but …

Optimal Synthesis Of Active Distributed Rc Low-Pass Filters, Robert Iman Egbert

Masters Theses

"Although synthesis procedures for active distributed RC networks are well developed, the approximation problem is largely unsolved. Previously proposed solutions have several disadvantages. A better solution to the approximation problem is obtained by developing an error expression involving the difference between the ideal specification and the exact realization, then minimizing this error by numerical techniques. The method is illustrated by designing a set of active distributed RC low-pass filters"--Abstract, page ii.

A Thin Film Evaporator Rate Controller, Daniel Robert Kasterlein

Masters Theses

"A circuit is described which is used to control the evaporation rate of material from a resistance heated boat or electron beam evaporator. The rate controller is used in conjunction with a quartz crystal thickness monitor in a vacuum evaporator"--Abstract, page ii.

Nutation Control During Precession Of A Spin-Stabilized Spacecraft, Richard James Donner

Masters Theses

"The effects of precession thrust pulses and energy dissipation upon nutation of a spin-stabilized spacecraft are studied. Methods for controlling nutation during a precession maneuver are proposed and examined. In particular, a precession modulation control law is developed which uses precession thrust pulses to control nutation. Digital simulations show that precession control with separate nutation control is the fastest precessing system; however, the precession modulation method is only fractionally slower while not requiring a separate nutation control system"--Abstract, page ii.

Design Of An Analog-Temperature Control System For An Expansion Cloud Chamber, Andrew C. Tebelak

Masters Theses

"This thesis describes the design, construction, and application of an analog control system for the temperature control of an expansion cloud chamber. During the expansion, the sample gas and the chamber walls are cooled at the same rate so as to maintain adiabaticity. The control system measures the wall temperature with transistor temperature sensors, calculates the gas temperature from the gas pressure using the adiabatic gas law, and generates a control signal proportional to their difference. The control precision is sufficient to allow the chamber to be used in the study of atmospheric phenomena.

The chamber is a ten-sided right …

A Study Of Rf Induction Heating And Float Zone Refining Of Silicon, John Allen Reynolds

Masters Theses

"Float zone refining using simultaneous RF induction heating and electromagnetic levitation has proven to be the best technique for producing high purity silicon for the semiconductor industry.

A study of the power requirements for floating molten zones, of load to source impedance matching, and of considerations for RF heating coil design was conducted to determine possible methods of improving the technique. It is shown that the power requirements are within reason, that impedance matching can be improved by varying network parameters, and that certain vital items must be assured in the design of different RF heating coils.

It is believed …

A Travelling-Wave Transistor Amplifier, Manit Kovintha

Masters Theses

"This thesis discusses a steady-state analysis and design of a coupled uniform travelling-wave transistor amplifier. A solution to the problem is given in closed form and a numerical method for evaluating the solution is discussed.

Practical line parameters and different terminations are used in frequency response calculations. The amplifier power gain variations due to parameter variations are considered and shown in full"--Abstract, page ii.

Inertial Navigation Performance Improvement Realized By The Technique Of Interrupted Alignment, Ralph E. Herndon

Masters Theses

"Present on-aircraft ground alignment gyro bias methods can basically be categorized as (1) periodic maintenance performed by the ground crew, (2) pre-flight calibration requiring a two-position gyro compass alignment or (3) optimal filter estimation of the north gyro bias error.

This thesis discussion presents an interrupted alignment method that allows adequate level axes gyro bias correction without the restrictions associated with a conventional two-position gyrocompass alignment (i.e., a minimum time for bias calibration on a steady aircraft). The interrupted alignment technique allows the pilot to select the navigate mode at any point during gyrocompass and reselect the align mode at …

Design And Construction Of An Electronic Pressure Altimeter For An Atmospheric Data Acquisition System, Larry Wayne Berkbigler

Masters Theses

"This thesis describes the design, construction, and application of an altimeter which was developed as part of the data acquisition system of a small aircraft used to study atmospheric conditions. The altimeter provides a digital readout and interfaces with analog and digital recorders. It can also provide an audio indication when a predetermined altitude is reached. The altimeter is powered by 12 volts dc, has resolution to 10 feet, and a maximum altitude of 15,000 feet. Its maximum theoretical error is ±78 feet ±0.77% of true altitude, which is an error of ±194 feet at 15,000 feet.

Since the unit …

A Suboptimal Control Law For Parametrically Disturbed Linear Systems And Its Application To Improve The Transient Stability Of Power Systems, Atluri Bhima Ranjit Kumar

Masters Theses

Paper 1: “A suboptimal linear control law is synthesized for parametrically disturbed linear systems, and the necessary approximation for applying the law to a class of nonlinear systems is given. The law is then extended to linear systems with stochastically disturbed parameters by using appropriate approximations”—Abstract, page 2.

Paper 2: “The application of optimal control theory to damp the electromechanical oscillations associated with the transient conditions in power systems has been given little attention. A suboptimal control law which minimizes the sum of the performance indices of the two linear systems given by a piecewise linear model of a power …

Numerical Calculation Of The Currents In Bent Wire Antennas, Min Ho Kang

Masters Theses

"The current distribution for bent dipole antennas is numerically calculated by using a digital computer. A delta-gap at the center is assumed for the drive. Several different bend-angles are considered including the cases of the straight wire and the inverted-L. The total length of the wire considered is λ/2 while the ratio of the bent portion over the vertical portion is varied. The method of solution is based on Mei's integral equation and the method of moments. The use of Mei's integral equation eliminates the need for the application of the boundary condition at the point of bending. For …

The Static Nonequilibrium Characteristics Of Planar Germanium Probes In A Slightly Ionized Hydrogen Plasma For Low Injections, Alfred Gene Williams

Masters Theses

"The theory for a planar semiconductor probe in a slightly ionized gas with small dc current densities is developed for a germanium probe immersed in a hydrogen plasma. First, the equilibrium characteristics due to the probe in the plasma are developed from Poisson's equation and current density equations. Then, the static nonequilibrium characteristics due to the probe are found by perturbing the equilibrium characteristics and substituting the perturbation terms into Poisson's equation and current density equations. The total current, I, is found to vary linearly with the applied voltages, V, and the ratios I/V are essentially the same for both …

Digital Fault Calculations Of Large Systems Using Matrix Language And Generalized Equations, Saeed Abdel-Halim Khalifa

Masters Theses

"A new short circuit program has been developed for a large system. Several features have been provided to simplify handling of the system data. Various study cases are performed, efficiently, within the available computer memory. A master data bank is established from bus, feeder and transformer data. They can be modified internally to simulate various system configurations. Matrix formation is accomplished using a new sorting method and the IBM/360 Matrix Language MATLAN. A generalized set of ii ·equations have been developed and applied to calculate four types of faults.

The program consists of two phases of operations. In phase-1, input …

Analysis And Design For Semi-Automatic And Automatic Control Of Vehicles By Permanent Magnets, Hari K. Mehta

Masters Theses

"The analysis and design carried out in this study relates to automatic or semi-automatic lateral control of a vehicle. This is one of the three essential subsystems needed for a complete automatic control system. The other two subsystems provide longitudinal control, and intersection or lane-changing control.

The system studied employs a series of permanent magnets which have been embedded vertically in the road and spaced at an interval to be used for position reference, leading to discontinuous error signal. This system has been analyzed by classical Z-transform analysis and control models have been developed for two kinds of controls. First, …

A Multivariable Sampled-Data Model Of An Automobile Driver, Jose A. Bermudez

Masters Theses

"In this thesis, a multivariable system model of driver performance in the basic driving tasks is presented. The driver model described acts as a serial-process, priority-accessed, time-sharing computer. This model processes the input or output task which currently possesses the highest priority. Input tasks are represented by continuous signals sampled intermittently according to priority laws. Output tasks are modeled as simple analog processes operating on the last few intermittently generated output controls. An individual priority rule is constructed for each input and output task.

The performance of the driver in the lateral control task involves a feedforward pattern which is …