Engineering Commons^™

Shutdown Reactivity Worth Of Reactor Control Rods By A Subcritical Multiplication Method, Leslie Roger Conner

Masters Theses

"Two modified subcritical multiplication methods for measuring the reactivity worth of control elements were developed and investigated. The first involved the calibration of a subcritical count interval by the asymptotic period method. The second involved the calibration of a subcritical count interval by a rod interchange with the reactor regulating rod which had previously been calibrated by the asymptotic period method. The accuracy of these methods is relatively poor. this inaccuracy is due to shadowing effects and to the spatial harmonics which exist in the core. An investigation of the spatial harmonics to determine the best location for the neutron …

Mass Transfer From A Torus Shaped Body, Kamalesh Suryakant Desai

Masters Theses

"A mathematical model for molecular diffusion in a torus was derived. Handlos and Baron have assumed a system of tori in their eddy diffusion model for liquid-liquid extraction from droplets. However, the effect of torus curvature was neglected in their studies. Since they assumed the torus could be represented by an infinite cylinder. In this study, the effect of torus curvature was considered on the concentration profile and the fraction of the solute extracted. The partial differential equation describing the model consists of three independent variables, and a finite difference technique was employed for the solution of the mathematical model. …

Plastic Deformation Of Thin Plates With A Spherical Indenter, Benjamin Jen-An Chang

Masters Theses

"A method of determining the stress distribution in a thin plate deformed with a spherical indenter is presented in this report. The analysis is formulated in cylindrical coordinates and utilizes the basic principles of plasticity (von Mises yield criteria, Luwig stress-strain equation, Hencky Deformation theory, etc.). The problem is solved through the utility of a displacement function that, by virtue of its definition, automatically assures that the condition of volume constancy is satisfied. The boundary conditions are selected on the basis of having average, or integrated, effects corresponding to the physical constraints of the problem. Numerical integration is introduced to …

Compressive Creep Of High Alumina Refractories, Vernon Lee Burdick

Masters Theses

"The deformation of refractory materials consisting of 90% sintered or fused alumina plus 10% silica was measured at temperatures from 1450 to 1515⁰C and a compressive stress of 100 psi. Creep rates and activation energies were determined from the steady state portion of deformation vs. time data and correlated with the mineralogical composition. Supplemental measurements included x-ray diffraction, electron probe microanalysis, apparent porosity and tensile strength. conditions having an important effect upon the mineralolgical composition were: (1) duration of heat treatment, (2) amount of sodium oxide impurity, and (3) reactivity of the alumina grain. Prolonged heat treatment and sodium oxide …

The Design Of A Drum Memory System, Frederick W. Lynch

Masters Theses

"Three methods for obtaining an auxiliary memory for an SCC-650 (Scientific Control Corporation) digital computer are presented. A logic design is then developed on the basis of using the drum and write circuits from an available IBM-650 digital computer and constructing the remaining logic functions. The results of the logic design are the transfer equations necessary to implement the memory system"--Abstract, page ii.

Some Effects Of Nickel On The Microbial Population Of Activated Sludge, Virgil Eugene Carr

Masters Theses

"The purpose of this investigation was to study the effects of nickel on the microbial population of activated sludge, to establish a relationship between effluent quality and changes in microbial population, and to determine the fate of nickel applied. Five one liter fill and draw activated sludge units were fed settled domestic sewage and received constant daily nickel doses of 1-10 mg/l, and a 50 mg/l slug dose applied after 27-30 days of operation. The parameters used were the chemical oxygen demand (COD) of the effluent and membrane filtered effluent, mixed liquor and effluent total suspended solids, mixed liquor volatile …

A Class Of Pattern Recognition Machines, Shaw Yih Chung

Masters Theses

"The classification of signals through the use of pattern recognition techniques may be viewed as a statistical classification problem since at least some pattern classes are analog signals which have been contaminated by additive noise. In order to represent these signals at the input of a pattern classifier they are sampled and a vector and an m-dimensional vector space used to describe the pattern. Consequently, these pattern samples are processed to determine the parameters of the statistics. In this study the additive noise was assumed to be Gaussian in nature. This study was based on a priori knowledge of the …

Synthesis Of Filters Using Distributed Rc Networks, Mario Nader Nader

Masters Theses

"This paper deals with the problem of realizing filter and delay functions by means of distributed RC devices. The method is made possible through the use of a distributed RC network which possesses rational admittance parameters. The technique of approximating transfer functions using polynomial factors that are ration in e[superscript (a square root of s] is explained. These factors are used to approximate the magnitude and phase characteristics for a low-pass filter. This filter is then realized using the admittance functions studied by Wyndrum, the "s->W" transformation, and Richard's theorem. Those factors are then used to approximate high-pass and …

A Kinetic Study Of Ti⁺³ Oxidation To Ti⁺⁴ In Hydrofluoric Acid Solutions, Kuo-Shein Shen

Masters Theses

"The purpose of this investigation was to study the oxidation rate of Ti⁺³ to Ti⁺⁴ in hydrofluoric acid solutions in the absence of air. The concentration of hydrofluoric acid was varied from 0.25 to 2.00 M and the concentration of titanium from 0.05 to 0.50 M. The temperature was controlled at 25⁰C. The reaction rate was relatively slow. In most instances, less than 50 percent of the Ti⁺³ was oxidized during a period of 100 hours"--Abstract, page vii.

Relationship Of Feldspar Properties To Surface And Volume Defects In Porcelains, Macy Wiiliam Vance

Masters Theses

"Four levels of particle size distribution and four compositions of feldspar ranging from high-potash to high-soda content were evaluated in their effect on body and surface defects and selected engineering properties of an electrical porcelain. It was found that surface blistering defects occurred at a high incidence in porcelain specimens slightly overfired at 1225⁰C in a body composition containing 33% albite (soda), 67% high-potash feldspar blend and a relatively coarse, 140 mesh grind, of the feldspar. The occurrence of surface and volume blisters was correlated with the formation of a microscopic bleb structure in the porcelain matrix. It was also …

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 …

Optimum Fin Spacing For Heat Transfer Per Unit Length Of Heat Exchange Section, Glenn Ellis Miller

Masters Theses

"This thesis presents the results of an experimental study of the heat-transfer ability of a finned surface as a function of the spacing between fins. The results are expressed as heat transfer per unit length of finned section rather than the heat transfer per fin. Circumferential steel fins, seven and three-quarter inches in diameter, were used for the investigation. Data was taken for fin spacings ranging from zero to one and one-half inches. The experimental heat-transfer rate to atmospheric air was determined by measuring the volume of saturated steam which condensed in the test section over a measured time interval. …

The Influence Of A Fixed Failure Plane On The Direct Shear Test, Kenneth Hodges Bell

Masters Theses

"The analysis of the direct or box shear test for determining the shear strength of a soil makes use of the assumption that the failure plane coincides with the plane of separation between the two halves of the box. Hvorsley, Roscoe, Hansen and others have theorized and experimentally shown that this is not always the case. The stress distributions on the failure plane, however it may be oriented, are not as uniform as generally assumed. This investigation was carried out to compare direct shear tests run on granular, air dry material where the failure was allowed to take place naturally …

Estimation Of Regional Trends In Gravity Using Gram Orthogonal Polynomials, Stanley Dean Thompson

Masters Theses

"A computer program is presented which estimates the trend in a rectangular array of gravity measurements. It is assumed that the regional trend of gravity may be estimated by a low-order polynomial. The method of least-squares is applied to solve for the low-order polynomial which best approximates this trend. Gram orthogonal polynomials are used in the solution of this least-squares surface fit. The program is tested on a known polynomial and on some hypothetical Bouguer gravity data and found to approximate the ʺregional trend of gravity in these cases. The importance of eliminating any significant noise in the observations before …

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 …

Design Of A Nonparametric Detector For Fm Signals, James Charles Fowler

Masters Theses

"The communication engineer has in the past treated the detection problem from a parametric point of view. That is, the signal has been assumed to be of a known deterministic form and the noise of a known statistical form. This approach has proved valuable in many cases, but it is subject to severe limitations, e.g., if either the noise or signal change form, a new detector must be designed. Because of these limitations there is a need to find a more general form of detector.

This study looks at a specific statistic (the Cramér-von Mises statistic) and designs a detector …

A Study Of Probability Of Error Calculations For Baseband Multi-Level Digital Transmission Systems Using The Fixed Threshold Decision Rule, Don J. Popp

Masters Theses

"This study is an investigation into analytical techniques used in deriving probability of error expressions for baseband multi-level digital transmission systems. A fixed-level decision rule is used to solve this statistical detection problem together with some simple concepts from probability theory. To illustrate these techniques, probability of error expressions are derived for the general uncoded system, a simple coded system, and a complex coded system. Curves of probability of error versus signal-to-noise ratio are plotted for the various systems considered"--Abstract, page ii.

Stress Analysis Of A Wall Footing Subjected To External Vertical Loads And Overturning Moments By The Finite Element Method, Adil Godiwalla

Masters Theses

"This investigation pertains to the stress analysis by the finite element method of a wall footing subjected to external vertical loads and external overturning moments. This problem has been reduced to a two-dimensional stress analysis problem by taking a unit length of the wall. A rectangular plate - element is used throughout this investigation. The development of the matrix equations is shown and the solution is performed by digital computer. Stresses in the horizontal direction show essentially linear variation which is in agreement with simple structural theory, while stresses in the vertical direction show severe perturbation near the column load. …

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 …

Study Of Mass Transfer Through Porous Water-Repellent Membrane As A Function Of Membrane Thickness And Rates Of Heating, Yalamanchili Babu Rao

Masters Theses

"The object of this investigation was to study the mass transfer coefficients through porous water-repellent membranes, and their dependence on membrane thickness and rates of heating, and to compare experimental correlations with theoretically based equations. The membranes used during the experimental work were made of glass fiber treated with Teflon suspension and aluminum sulfate. The mechanism involves evaporation and condensation on opposite sides of a vapor-filled porous membrane. Salt water evaporates from one interface of a non-wettable, porous membrane, diffuses through the vapor filled pores, and condenses to fresh water at the other interface of the membrane. This transfer may …

Computer Solutions To Depletion Drive Hydrocarbon Systems, Tu Kao Chen

Masters Theses

"Three computer analyses of oil production by depletion drive have been developed. These analyses, Tarner's method of depletion drive oil production prediction, depletion drive performance productions of Schilthuis, and depletion drive calculations by a finite difference material balance, have been programmed for computers having Fortran IV compilers and a minimum of 40 K bytes of core storage capacity. Modifications have been incorporated in the last two techniques for (a) constant volume injection of produced gas, (b) the presence of a gas cap, (c) gas-cap injection of produced gas volumes, (d) varying water encroachment and production, and/or, (e) varying sweep efficiencies …

The Recovery And Characterization Of Organic Micropollutants From Missouri Subsurface Waters, John Warren Smith

Masters Theses

"The main objectives of this investigation were the recovery and partial characterization of organic micropollutants from Missouri subsurface waters and the evaluation of the number of filters in series required for effective removal of organic materials from water using the Carbon Adsorption Method.

The organics were recovered from a spring and two deep wells using three large capacity (1. 5 cu. ft.) activated carbon filters in series. Chloroform and ethanol were employed as primary elutants, but acetone and benzene were also investigated. Characterization was by organoleptic, chemical, and biological determinations, toxicity measurements, and solubility partitioning.

Organic materials were found in …

Vapor Pressure And Evaporation Coefficient Of Cadmium Oxide, R. Tom Coyle Jr.

Masters Theses

"Knudsen effusion experiments were carried out on CdO in fused silica crucibles at temperatures of 918°K, 1008°K with orifice areas from 2.742x10^-3 cm² to 30.52x10^-2 cm². The experiments were made in a molybdenum-wire, resistance-heated vacuum furnace. Several orifice areas were used at each temperature and reciprocal pressure versus orifice area plots were made. These plots yielded an upper limit to the evaporation coefficient of. 4.15x10^-2. An equilibrium constant for the vaporization reaction

CdO(s) = Cd(g) + 1/20₂ (g)

of

log Keq = 11.12 - 1.952x10⁴/T.

was obtained. Second and third …

Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Surendra V. Desai

Masters Theses

"The object of this investigation of molecular diffusion in aqueous polymer solutions was to study the effect of solute concentration on the differential diffusion coefficient and also to study the effect of polymer concentration on the mean integral diffusion coefficient. For this purpose a microinterferometric method was used. Two non-ionic, water soluble polymers, Carboxymethylcellulose (CMC) and Carboxypolymethylene (Carbopol), were used in the study with D-Glucose as a solute.

The differential diffusion coefficient was found to increase with increases in solute concentration in all cases. For CMC, the integral diffusion coefficient at first decreased with increasing polymer concentration but became constant …

Dynamic Response Of A Simply Supported Beam To An Accelerating Point Load, Joseph Victor Cusumano

Masters Theses

"An analysis based on linear theory is presented for determining the dynamic response of a simply supported beam on an elastic foundation acted upon by a moving time dependent point force with axial forces included. This thesis extends the present theory to include an analysis of a point force accelerating uniformly across the beam. In particular, it is shown that the customary resonance conditions which are prevalent for a point force moving with uniform velocity no longer exist for the case of a point force accelerating uniformly across the beam.

The basic problem and its solution are presented for a …

Gap-Graded Gravel For Asphaltic Paving Mixtures, Ernest Harrington Martin

Masters Theses

"The objective of this investigation was to determine if naturally occurring gap-graded gravel can produce asphaltic mixtures meeting minimum requirements for satisfactory pavement behavior.

Ten gap-graded mixes were blended by eliminating certain intermediate sized fractions or combination of fractions from the gradation of a control mix. The weight of the fractions eliminated was distributed to either the coarser or finer aggregate fractions.

All specimens were prepared and tested in strict accordance with procedures set forth in ASTM Designation D1559, "Resistance to Plastic Flow of Bituminous Mixtures Using Marshall Apparatus."

The physical properties compared and analyzed were (1) unit weight, (2) …

Stresses In A Thick Spherical Shell, David Wayne Moore

Masters Theses

"This thesis reports a method to evaluate the stresses in a segment of a thick spherical shell. In the numerical examples loads due to thermal expansion as the shell is constrained at the free edge and a dead load acting vertically downward were considered for a shell assumed pinned but free to rotate and for a shell assumed completely fixed at the edge. A concrete shell was specifically studied but the method would also apply to a shell of any homogeneous, isotropic material"--Abstract, page i.

Small-Signal Impedance Of A Junction Diode At High Injection Levels, John E. Lundy

Masters Theses

"A mathematical expression for the driving point impedance of a junction diode at high injection levels is developed. To evaluate the impedance versus frequency characteristic of a diode, it is necessary to know the minority carrier lifetime as a function of injection level and doping density in the base (lightly doped) region, the junction area, and the base width. The interesting characteristic of the diode impedance at high injection levels is the inductive reactance displayed by the diode.

The expression is developed by solving the differential equation for charge flow in the base region of a diode assuming space-charge neutrality …

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.

Convective Heat Transfer In Small Cylindrical Enclosures Heated From Below, Donald Wayne Land

Masters Theses

"Free convection in enclosed air spaces is often of prime importance in the design and analysis of panels utilizing the insulating properties of air and other gases. Previous investigations were performed on very thin air layers.

This thesis presents the results of an experimental investigation to determine the heat transfer by convection and conduction through air layers with relative sizes in terms of length/diameter ratios of one-fourth to one.

Eight cylindrical samples were tested. Four had inside diameters of 2.0 inches, and the others were 2.75 inches in diameter. Heat was transferred across the air layers by both conduction and …