Digital Commons Network^™

An Experimental Study Of Power Systems, Nguyen Quang Duoc

Masters Theses

"For three phase AC power systems consisting of synchronous machines interconnected by transmission lines and other electrical transmission equipment, the power transmitted and the stability of the system depend upon the constants of synchronous machine and the characteristics of the transmission lines. The purpose of this work is to design and set up a model of a power system in the laboratory, measure the constants of synchronous machines, the power angles and power flows of the system. An investigation of the effects of the saturated machines is based upon the laboratory data.

This work is intended primarily as a tool …

Design Of A Digital Control Unit For A Seismic Digital Tape System, Cao-Van Chung

Masters Theses

"This paper describes the interface between the NOVA digital computer and the Texas Instrument tape unit which handles field data recorded simultaneously from a maximum of 31 channels. The interface is the means through which the NOVA computer can control the tape unit and recover data. To provide necessary background information a review of the characteristics of the tape unit and the input-output operation of the NOVA computer are given. As the first part of the design, the general interface design is presented and the functions of its units are described. After discussion of functional assignment of each unit, coordination …

A Sensitive Temperature Measuring System, Larry Dean Morris

Masters Theses

"A sensitive temperature measuring system, providing an analog output proportional to sensor temperature, has been designed for use in the wall temperature control system of a cloud simulation chamber. A platinum resistance element is the sensor, and a precision wirewound resistor is the reference in a bridge circuit which uses four low cost operational amplifiers arranged to provide two precision 1000 Hz current sources. Problems with an initial bridge amplifier design were corrected in the final design by the use of a low Q bandpass amplifier for the bridge signal followed by a phase detector and an output low pass …

High Speed Magnetically Supported Vehicles For Reducing Transportation's Degradations Of The Environment, Pravinchandra Shukla

Masters Theses

"The development of new techniques for higher speed transportation is desirable to satisfy the environmental, conservation, and economic requirements of society. Some of the important factors are presented for developing magnetically supported vehicles. A new method for improving the ratio of lift force to drag force is suggested and discussed. An application of the new technique to vehicles that would ride on a carpet of magnetism and would operate with less waste of energy is suggested "--Abstract, page ii.

A Study Of Plane Wave Filter Analysis With Flow, Thomas Valle Huber

Masters Theses

"The purpose of this investigation is to determine the effect of slow steady flow on the reflection and transmission characteristics of acoustic filters.

A standing wave tube and transmission tube apparatus, designed and built by a previous investigator, was modified to accept slow steady flow. Reflection characteristics were determined from measurements made on the inlet side of the filters investigated. These data along with measurements taken with the transmission tube apparatus were used to determine transmission characteristics. The calculations were simplified by terminating the filters anechoically. The filters used in this investigation were an expansion chamber, an automobile type muffler …

Digital Registration Of Stereo Images Using The Fast Fourier Transform, Victor Francis Wilreker Jr.

Masters Theses

"The exact alignment of multispectral imagery is a requirement of any image classification system. This investigation develops a system of programs which result in a technique that corrects for the translational and rotational misalignment of two images. Rotational and translational components are determined by using the fast Fourier transform to find the points of maximum correlation between the two images. The registration of two equal but misaligned boxes is given as an example of how the transform technique is used in correlating the images. The results of registering two digitized images that were obtained by scanning a pair of color …

Laboratory Studies Using Diffused Oxygen And Air For Hypolimnion Reaeration, Chin-Ming Pai

Masters Theses

"The purposes of this research were to study the oxygen transfer rates and the oxygen transfer efficiencies of different types of aerators using different sources of oxygen in different types of water bodies, and to evaluate the number of diffusers required to be installed in a selected lake for hypolimnion aeration.

The experiments were conducted using a specially designed column. Four types of aerators, including a cylindrical stone diffuser, a spherical stone diffuser, and 2 ceramic diffusers (types A and B) which differed in pore size, were utilized as the aerators. The water bodies selected for the studies were Rolla …

The Morphology Of The Cellular Precipitation Reaction In A Pb-3.0 Wt% Sn Alloy, Federico Sequeda Osorio

Masters Theses

"The complete development of the cellular precipitation structure at selected grain boundaries in a Pb-3.0 wt% Sn alloy during aging at 34°C and 23°C was investigated by light microscopy. The cellular structure in this alloy consists of lamellae of solute depleted lead solid solution and lamellae of ß tin precipitate. The cellular precipitation reaction begins by local migration of a grain boundary with concomitant grain boundary precipitation of ß tin. The grain boundary bows around the ß tin grain boundary precipitates which then begin to lengthen in the direction of boundary migration thus forming the precipitate lamellae of the cell. …

Polynary Silicon Tellurium Glasses, Henry Edward Anthonis

Masters Theses

"The introduction of Ag into Si-As-Te glasses permits the incorporation of Se, otherwise volatile and/or degradable as a constituent in Si-containing chalcogenide glasses. Si-As-Ag-Te-Se glasses exhibit much higher softening ranges and glass transition temperatures than encountered in known chalcogenide systems. A glass Si₃₅As₁₅Ag₁₀Te₂₀Se₂₀ had the viscosity log η =13 at about 500°C, as compared to 370°C for the base glass Si₃₅As₂₅Te₄₀, the viscosity of log η = 9.8 at about 560°C, as compared to 442°C for the base glass Si₃₅As₂₅Te_{40 …}

Studies Of Neutron Capture Produced Rare Gas Isotopes In Rocks And Minerals Containing Chlorine, Selenium And Tellurium, David E. Sinclair

Masters Theses

"Noble gas mass spectrometry was used to study rare nuclear processes in terrestrial rocks and minerals. An excess of ³⁶Ar was detected in a chlorine-rich rock. The excess ³⁶Ar has been produced in rocks near the earth's surface due to capture of cosmic-ray-produced neutrons on ³⁵Cl. Measurement of ³⁶Ar formed by the ³⁵Cl(n, γ)³⁶Cl(β^-)³⁶Ar process makes possible a new method for determining the surface residence time of chlorine-rich minerals

Excess ⁸²Kr and excess ⁸³Kr were detected in selenium-rich ores. The excess ⁸²Kr results from double beta …

Effect Of Glass Aggregates Upon Abrasiveness Of Asphaltic Mixtures, Dwarka Prasad Gupta

Masters Theses

"The utilization of glass as an aggregate in asphaltic concrete pavements has been suggested as a means for reusing the increasing amounts of waste glass generated each year in the United States. Recent studies have shown that asphaltic mixtures containing glass aggregates can be designed to meet Marshall requirements for stability, flow and void content but the abrasiveness of mixtures containing glass aggregates had not been investigated. The objectives of this study were to develop a laboratory wear testing apparatus and compare the abrasiveness of asphaltic concrete mixtures using glass aggregates with the abrasiveness of mixtures using several different conventional …

Design And Construction Of A Drop Generator For Use In A Vertical Wind Tunnel, Danny Ray Conner

Masters Theses

"A drop generator, based on the principle of a vibrating capillary, was designed and built for use in the UMR vertical atmosphere wind tunnel. The drop generator worked very well on a test stand where it was firmly supported, but was not consistent when tested in the wind tunnel. Vibration of the wind tunnel walls and a slight turbulence near the forward edge of the generator caused an oscillation in the position of the stream of drops. The oscillation resulted in some of the drops hitting the edge of the collector cup, where the drops would accumulate until a large …

Computer Simulation Of The Primary Recoil Spectra And Damage Cross Section Of Fe₃Al Using Endf/B Ii Data, Daniel Willard Smith

Masters Theses

"A computer program, using Evaluated Nuclear Data File (ENDF/B II) information, was used to develop energy-exchange kernels which delineate the energy transfer probabilities between neutrons and Fe₃Al lattice atoms. The kernels combine all available information on elastic and inelastic scattering contained in the ENDF/B II data.

The computer program used to generate the primary recoil spectra is SAKI, a modified version of RICE (1). SAKI is designed to calculate energy-exchange probabilities in any binary alloy as well as damage cross sections and optimum cutoff energies for use in comparing displacement effects in different reactor spectra."--Abstract, page ii.

Design Of A Torsional Vibration Machine, Prafulchandra Pragjibhai Desai

Masters Theses

"In this thesis the design of the major components of a torsional vibration machine is presented. The machine is a torsional vibration actuator which will deliver a mean output angular velocity with a superimposed harmonic component. This type of motion can be used to study the torsional vibration characteristics of models representing crankshafts, gear trains, torsional dampers, and other systems. The primary machine elements of the actuator are a power source, flywheel, and a Hooke's joint. The power source consists of a D.C. shunt motor and a drive transmission using 3 V-belts. Through the use of a Hooke's joint, approximate …

Equilibria Between Moo₂ And Liquid Molybdenum Oxide, Prakash Bakhru

Masters Theses

"The oxygen pressure over solid molybdenum dioxide in equilibrium with liquid molybdenum oxide was determined by transpiration and solid electrolytic galvanic cell methods at 950ºC and 900º, 950º and 1000ºC respectively. The results were compared to those expected from thermodynamic data on the Mo-O system. Possible reactions between MoO₂ and SiO₂ were studied at different oxygen pressures up to 1550ºC. No compound formation or solid solution between MoO₂ and SiO₂ was detected by x-ray diffraction techniques. The phase boundary between MoO₂ and liquid molybdenum oxide was checked by microscopic examination of quenched samples. Equilibration runs were carried out in silica …

Calculation Of Buildup Factors For Multilayer Slab Shields Using The Monte Carlo Method, John Paul Kuspa

Masters Theses

"Gamma-ray beams normally incident upon slab shields of varying compositions are studied using a computer program based upon the Monte Carlo technique. Initial gamma energies of 1, 4, 6, and 8 MeV are considered. The shielding materials used were aluminum, iron, and lead. Both single and double material shields were investigated, at a variety of thicknesses up to a maximum of five mean free paths. Two secondary gamma processes are included in this simulation: annihilation gammas from pair production and bremsstrahlung from the electrons. The primary effort is the calculation of the dose, energy, and number buildup factors for these …

The Effects Of Intense Sound Levels And Steady Flow On The Propagation Of Plane-Waves In Air, Wuu Hao

Masters Theses

"This thesis is a theoretical investigation of the effects of intense sound levels and steady flow on the propagation of plane-waves in tubes of constant diameter. The analysis is limited to a study of the change of wave profile due to the intense sound levels, and steady flow. However, corrections for effects of viscous and heat conduction losses at tube walls are also presented. To simplify the analysis, the problem is treated by considering the steady flow and finite-amplitude-sound wave effects separately. For finite-amplitude sound only, two approaches are evaluated. The first uses small perturbations to derive a finite-amplitude wave …

Effect Of Biological Activity On Pesticide Desorption, Loh-Tien Chiang

Masters Theses

"The purpose of this research study was to investigate the effect of biological activities on the desorption of pesticides from humic acid solids. The pesticides selected in this study are dieldrin and heptachlor, both of which have been commonly used in agricultural applications. The humic acid adsorbent was extracted from a coal-like substance called "leonardite", which has a humus content of as high as 53 percent by weight. The first step of this study involved a proper cultivation of biological culture so that the culture could be adapted to a test environment containing a high concentration of humic acids. The …

A Comparison Of Analytical And Experimental Approaches In Determining The Thermoelastic Stresses Around A Cylindrical Inclusion Of Elliptical Cross-Section, Kenneth Byron Oster

Masters Theses

"Three approaches are used to determine the principal stress differences in an infinite elastic medium containing a cylindrical inclusion of elliptic cross-section due to a uniform temperature change. First, the two-dimensional equations of thermoelasticity are solved resulting in equations for the stress components anywhere in the medium material. Second, boundary displacements based on stress-strain relations are used as input displacements in a finite element program of the medium. Third, these same boundary displacements are used as input displacements on a photoelastic model simulating the medium. The problem is treated as one of plane strain in the first approach and one …

Managerial Success And Personality Traits Of Self-Actualization, Louis H. Ballenger

Masters Theses

No abstract provided.

An Analysis And Annotated Bibliography Of Selected Books For Children About Negro Life, Dorothy L. Stevens

Masters Theses

No abstract provided.

Medieval English Urban Social History: A Search Through The Chronicles, Willard T. Wolff

Masters Theses

No abstract provided.

An Experimental Study Of The Effects Of Classroom Photography On The Self-Concepts Of Culturally Disadvantaged Sixth Grade Students, Donald L. Wetmore

Masters Theses

No abstract provided.

Adaptation To The Functional Loss Of Pinnae In Sound Localization Ability, Marvin Richard Navarro

Masters Theses

No abstract provided.

A Study Of The Effects Of A Reading Program For Reluctant Readers, Florence Evelyn Banks

Masters Theses

The purpose of this study was to obtain some statistical evidence concerning the effects of a reading program for high school students rated as reluctant readers on their reading habits and attitudes. The initial problem which motivated the study was that assignments to read novels were resisted by this group. The students can read, but do not.

The hypothesis is that if students are given a program with books of 200 pages or less that have in the content some universalities that will satisfy the adult interests of students, attitudes about reading will change and there will be an improvement …

A Study Of The Materials Used In The Teaching Of Reading By Teachers With And Without A Library-Media Center With A Full-Time Media Specialist, Mary Ann Paulin

Masters Theses

No abstract provided.

A Process Study: Developing An Elementary Language Arts Guide, Norma Korn

Masters Theses

No abstract provided.

Waldensians And Franciscans A Comparative Study Of Two Reform Movements In The Late Twelfth And Early Thirteenth Centuries, Stanley D. Pikaart

Masters Theses

No abstract provided.

Three Variations In The Administration Of The Cat, Margot E. Warren

Masters Theses

No abstract provided.

A Comparative Study Of The Helminth Fauna Of Salmo Gairdneri Rich. From Three Different Environments: A Hatchery, A Lake And, A River, Jose Felipe Ribeiro Amato

Masters Theses

No abstract provided.