Engineering Commons^™

Safe Thermal Operation Of Power Transistors Under Pulsed Excitation, George R. Swain

Electrical and Computer Engineering ETDs

One desires to find the relationship between thermal stability and such factors as temperature within the transistor, power dissipation in the transistor junctions, collector saturation current, and thermal resistance. In the approach set forth in this paper, the theory of solid state heat flow is applied to a simplified thermal model of a power transistor.

A Design Of Los Esteros Flood Control Dam, Constantine G. Hadjidakis

Civil Engineering ETDs

This thesis covers a preliminary design of the Los Esteros Dam based on limited subsurface investigations and laboratory testing. This earth-filled dam will be 222 feet high and will have a top width of 20 feet.

A Transient Thermal Analog Of Nuclear Reactors, James R. Hume

Nuclear Engineering ETDs

The nuclear reactor is presently receiving considerable attention as a possible source of energy for stationary power plants and propulsion systems. This has stimulated interest in many engineering problems which become very significant in reactor design work. The response of the reactor core heat transfer system to changes in power generation is one of these problems.

The Design, Construction And Testing Of An Electrical, Transient Heat Flow Analyser, Bruce Wilcox

Electrical and Computer Engineering ETDs

The purpose of this investigation was (a) to design and build an analog which would produce the solution to a simplified yet typical transient aerodynamic heating problem, (b) to obtain the solution using the analog and to check the accuracy of the solution by mathematical computation, and (c) to code a more involved aerodynamic analog.

Comparison Of Observed And Calculated Near-Vertical Radar Ground Return Intensities And Fading Spectra, James Arlin Cooper

Electrical and Computer Engineering ETDs

The study of ground-to-air terrain return is necessary in order to understand the functioning of radar altimeters.

Radar return at vertical incidence can be considered to be composed of two components. One, whic his returned by a mirror-like action, is called the specular component. The other, termed scatter, is due to diffuse rerediation from individual scatterers on the ground.

In recent work on return from angles near vertical, more attention has been given to the scatter component than many had previously assumed necessary.

Procedure for Gathering Data:

Two pulse radar units were used, one having a frequency of 3.8 KMC, …

The Design Of A Solar Powered Air Conditioning System For An Albuquerque Office Building, Kuo S. Lee

Mechanical Engineering ETDs

The purpose of this investigation is to predict the performance of a solar powered jet refrigeration system for summer air conditioning, to measure the performance of the solar heat collector at the Bridgers and Paxton building in Albuquerque, and to design a Freon-12 ejector and generator for collection to that collector.

The Design, Construction And Investigation Of A Water Gravity Wave Analog Of Two-Dimensional Compression Waves In Gases, John H. Tenbrink

Mechanical Engineering ETDs

The purpose of this investigation was to design equipment for investigating and demonstrating supersonic air flow using water; to fabricate, assemble and calibrate this equipment; and to obtain and evaluate data on the validity of the supersonic flow analogy and the range of the equipment for classroom use.

Design Of An Experiment To Separate Specular And Scattered Radar Returns, Robert B. Glascock

Electrical and Computer Engineering ETDs

This paper describes the design of a radar experiment that will be conducted by the U.S. Naval Research Laboratory at Washington, D.C. The proposed experiment and the background of the problem are discussed, as well as the theoretical background, experimental background, and other design considerations are discussed in later sections.

Analysis Of Cushioned Impact By Wave Propagation Techniques, Lowell P. Martin

Mechanical Engineering ETDs

A typical problem of wave propagation which has received substantial attention concerns the longitudinal vibrations of a long, slender, uniform elastic rod after it has been dropped on one end.

The purpose of this investigation was to extend the problem to include the effect of cushioning material attached to the impacting end of a rod similar to that described above; and to conduct experiments designed to verify the analysis. This study is essentially the first step toward the analysis, by wave propagation methods, of many practical impact problems encountered in military airborne operations, experimental rocket programs, and the packaging industry.

A Study Of The Reset Cycle Of A Half-Wave Self-Saturable Magnetic Amplifier, William W. Lee

Electrical and Computer Engineering ETDs

It was the purpose of this study (1) to investigate the reset cycle of a half-wave self-saturable magnetic amplifier by graphical analysis of the irregular voltage functions appearing across the gate winding during reset; and (2) to determine if possible from this analysis a more satisfactory design method than those now available. Conditions of constant current reset were employed and the core material used had a nearly rectangular hysteresis loop. Resistive loads only are considered.

A Study Of A Complementary Symmetrical Power Switching Circuit, Glenn S. Mills

Electrical and Computer Engineering ETDs

This paper contains an analysis of a symmetrical, complementary, power switching circuit employing complementary power transistors. A DC analysis is made for the bistable states. Also described is a voltage regulation and bias circuit which improves stability and contributes to the protection of the transistors. The problem of switching transients is investigated and empirical results presented to support theoretical considerations. A new triggered method is proposed to utilize the bilateral characteristics of a transistor. Applications of the circuit are suggested for controlled-frequency and self-triggering modes of operation. A method and analysis for self-triggering is presented. The advantages of this power …

The Use Of Electrical Resistance Strain Elements In Three-Dimensional Stress Analysis, Robert I. Brasier

Electrical and Computer Engineering ETDs

The purpose of this thesis is to present a new method of experimental stress analysis and to give the solution to a problem which has been handled by this method.

Utilization Of The Relationship Between The Complex Immittance And The Indicial Immittance Functions For The Synthesis Of Two Terminal Networks, Julian T. Lefler

Electrical and Computer Engineering ETDs

It was the purpose of this study (1) to develop a new method of network synthesis from a specified complex immittance function; and (2) to demonstrate the application of the method by means of its use in the solution of representative synthesis problems. This work deals only with the synthesis of two terminal networks containing linear, passive, lumped-constant elements, from given rational immittance functions of the complex frequency variable.

Not considered part of this work are (1) the development of the immittance function from frequency-response specifications (the approximation problem); or (2) the treatment of active, non-linear, or time varying network …

Determination Of Q Factors And Operating Characteristics For Microwave Cavities And Oscillations, W.P. Stearns

Electrical and Computer Engineering ETDs

This paper has as its objective the presentation of the theory involved and method used with respect to the resonant cavity parameters; loaded Q, unloaded Q, external Q, pulling figure, and circuit efficiency for the resonant cavity investigated. Experimental data on a particular cavity are discussed and the previously mentioned cavity parameters determined with the use of such data and the particular method presented. A Rieke diagram for the particular cavity investigated is also presented and discussed.

Construction Of A Heavy Duty Military Airfield On Permafrost., Owen N. O'Leary

Civil Engineering ETDs

An examination of the map of the northern hemisphere will show that the two great population areas of opposing ideologies are located across the arctic regions from each other. This fact has been recognized by the U.S. military authorities since the early 1940’s, and an effort has been made to locate military forces in these regions to act as a possible deterrent to any aggressive action. The nature and geography of this region generally preclude any military forces except combat airfield. The most outstanding and possible only example of a major military airfield located entirely on permafrost material in these …