Digital Commons Network^™

Finite Element Analysis And Program For Stokes Fluid Flow, Jeffrey Steele

Theses

The theory and computer program for finite element analysis of Stokes (creeping) fluid flow is presented. The element is an eight node, two dimensional isoparametric quadrillateral. The element is formulated directly from the Stokes equations of motion, a special case of the Navier-Stokes equations where inertia terms are dropped, using the method of weighted residuals with Galerkin's criterion applied. Velocities in two directions are solved for at all eight nodes while pressure is solved simultaneously at the four corner nodes only. Several test cases have been run with the program. Very good accuracy was achieved in modeling velocity profiles for …

A Modification Of The Fourier Transform Model In Visual Perception, Bruce Apgar, William Harris

Theses

As for photographic systems , the human visual system can also be described by an MTF. However, due to the complexity and non-linearity of the visual system, the MTF alone is a poor predictor of response. We have formulated and tested two mathematical models which modify the MTF of the eye. Effectively, an imperfect integrating function (low pass filter) has been proposed to be operating on stimuli which are sent to the brain. The models were tested and found to be better predictors of visual response than the present MTF alone.

Solution Of The Transonic Potential Flow Equation By Finite Differences For The Hydraulic Analogy, Ewan Choroszylow

Theses

A numerical procedure is presented for the solution of the transonic potential flow equation around an isolated airfoil, for the hydraulic analogy. The numerical method used was the finite difference method, appropriately modified for a mixed elliptichyperbolic system of equations. Potential flow analysis was used, since for all practical purposes, the flow is inviscid throughout the flow field, except for wake regions and boundaries. The mixed finite difference scheme has proven to be an effective technique in the solution of elliptic and hyperbolic flow problems. For conditions near the wave propagation velocity (sonic velocity), difficulties have arisen in proper solution …

The Development And Utilization Of A Radio Station In The Secondary School, Daniel P. Bretch

Theses

Not available.

The Influence Of Bromide And Polyethylene Oxide Upon Development Kinetics, Robert Durbin

Theses

It has been previously reported that the speed and contrast of a given film-developer combination is influenced by the addition of PEO to either the developer or to the emulsion. Factorial experiments were conducted upon Ag(Brl) and Ag(BrCl) films to determine the PEO development effects on hydroquinone and N-methyl-p-aminophenol developers of normal sulfite level. Various levels of exposure, bromide concentration, and PEO addition to the developer were employed to gain information about possible interactions as well as individual effects. Density-log time of development curves were obtained using the method of arrested development. Response variables were induction period and maximum rate …

An Evaluation Of The Primary Factors Which Influence Proportionality Failure, Daniel Levine

Theses

If practical colorants could be found to meet theoretical requirements then there would be no need for color correction in multi-color printing. Color correction is necessary because the available yellow, magenta, and cyan inks absorb and transmit in all parts of the visible spectrum. It is possible to measure how much these colorants deviate from the ideal with the use of a reflection densitometer. The red, green, and blue filter positions on a densitometer will read the cyan, magenta, and yellow densities respectively. From these densities the amount of color correction necessary to compensate for the inks deficiencies is expressed …

The Pre-Setting Of The Ink Distribution Keys Of A Small Sheet-Fed Offset Press, Bruce May

Theses

The problem is to devise a system of pre-setting the ink keys of a sheet-fed offset press in order to save make-ready time. A preliminary experiment is run to establish and identify the correlation between the information obtained from visually scanning the plates and the ink key dial settings. The test involves a control group and a test group making press runs to see if pre-setting the ink keys can save time. The results show that such an idea is possible. The preliminary experiment establishes a positive correlation between the two variables and test group press-run times are significantly less …

A Quantitative Method Of Pre-Setting The Ink Distribution Keys Of An Offset Duplicator Using A Photoelectric Estimating Unit, Martin Marino

Theses

The purpose of this study was to study the feasibility of quantitatively pre-setting the ink key distribution on an off-set press. Presently the pre-settings of the ink keys has been left to the pressmens' ability and experience. This, in many cases, involves much "trial and error" work along with lengthy makeready times. This study attempted to reduce makeready time by quantitatively pre-setting ink keys from data obtained from an estimating unit and use of a set of calibration curves. A photoelectric estimating unit was designed and constructed to read integrated densities of copy to be printed. There was one reading …

The Influence Of Test Colors On The Color Rendering Index Maximization In A Three Component Spectral Power Distribution, Gregory Miller

Theses

This thesis describes the technique of principle component analysis as applied to determining if a combination of three characteristic vectors would account for an underlying structure in the eight color test objects specified by the CIE for calculation of the color rendering index (CRI). Anticipated was that three vectors would account for 100 % of the variance in the eight test objects; however it was determined that three vectors account for only 96 % of the variance. Since the analysis of the reflectance functions showed no dependence within the functions a 3^3 factorial experiment was conducted. Its purpose was to …

Image Intensification By A Low Level Light Exposure Before, During, And After An Image Exposure, Robert Rippstein

Theses

The purpose of this thesis is to study the effects on the shape and position of the characteristic curve due to a low level uniform exposure to white light. This was accomplished using a special camera which produced an image of a neutral density -wedge on a film strip. One half of this image was covered while the other half was uniformly exposed to a low level light exposure. In some cases the low level exposure was first applied to half of the film strip with the image exposure occurring second. The density differences between the two halves of the …

Interimage Effects In Various Subtractive Color Materials, Philip Wychorski

Theses

In three color photographic processes the cyan dye image is usually controlled by the red sensitive emulsion, the magenta dye image by the green sensitive layer, and the yellow dye image by the blue sensitive layer. Due to the proximity of these three layers in a color film interactions among the images are found to occur. It has been found that when the images are combined into a three color picture they do not have the same characteristics as they would have if they occurred separately. The density produced in each layer depends not only on the amount of exposure …

Calculation Of The Time Averaged Optical Transfer Function By The Fast Fourier Transform, Jan Pierce

Theses

The fast Fourier transform is used in two-dimensions to calculate the apodizing effect of a center opening pupil shutter. Two shutter models are investigated and compared, a circular shutter with diameter a function of time, and a five-bladed leaf-type shutter. The influence of shutter shape, defocus, and third and fifth order spherical aberration on the time-averaged optical transfer function is investigated. The results indicate that there is only a small effect on resolution and depth of focus due to shutter motion in a well corrected optical system.

Tumbling Through Time: An Inquiry Into Vision, Charles Fisher

Theses

None provided.

An Investigation Of The Electrooptical Properties Of A Dipole Suspension Of Iodoquinine Sulfate, Michael Smalter, Roy Dohlen

Theses

The objective of this thesis is to investigate the electrooptical properties of a dipole suspension. A dipole suspension consists of needle-like crystals which, in the presence of an electric field, orient themselves parallel to it. If the dipoles align themselves parallel to incident light, the suspension will transmit the light. If no electric field is present, the dipoles are in a random state, and little light is transmitted. The projected area of the dipoles is smaller when they are in the aligned state. Commercially, a dipole suspension is available from Marks Polarized Corporation as the product Varad. This thesis will …

A Suite Of Color Images Printed By Screen Process, Pamela Brueckner

Theses

None provided.

Experimenting With Varied Learning Environments In A Traditional Setting, Linda Stanford

Theses

This study, titled "Experimenting with Varied Learning Environments in a Traditional Setting," explores the integration of alternative and open classroom strategies within a conventional fourth-grade classroom in suburban St. Charles, Missouri. Conducted by Linda Stanford in partial fulfillment of her Master of Arts degree at Lindenwood College in 1976, the research investigates how varied learning environments—such as learning centers, student choice activities, and peer teaching—affect student attitudes toward learning, the teacher, and their own learning styles.

The study implemented five experimental activities: Reading Choices, a Language Block with multiple learning stations, Math Games taught to younger students, thematic learning centers …

A Study Of Practical Application Of An Activities Approach In An Educational Setting, Dennis C. Lane

Theses

Unavailable.

A Metalsmith's Guide To Toxicology, Margery Beth Rose

Theses

Not listed.

Large Deflection Of Thick Elastic Belts, J. L. Sisson

Theses

Not listed.

Distinguishable Density Levels In Image Recording Of Earth Resources Satellite Data, Steven Beiser

Theses

The Earth Resources Technology Satellite (ERTS) system produces a large volume of images of the Earth, with exposed film as the final output. These Images are presented to the user in pictorial form for interpretation and analysis. Specifications for this output film include MTF requirements, development method requirements, geometric tolerance and the number of DDL's (distinguishable density levels). Given the specification of 64 levels of gray, with a minimum density range of 2.0, the following investigation is warranted. Using theoretical calculations, granularity will be determined at different density levels. Assuming that Selwyn's Law is valid for the range of apertures …

Application Of The Finite Element Method To The Solution Of Maximum Fillet Stresses In Loaded Projections, Victor Biller

Theses

This thesis analyzes a geometric configuration under a loaded condition and establishes location and magnitude of the maximum fillet stress by the use of the Finite Element Method. Results are compared to Heywood's published study.

Identification Thresholds Of The Human Visual System For An Alphanumeric Resolution Test Object, Mark Bobb

Theses

Many investigations of the detection threshold of the human visual system have been conducted, and a few recognition threshold studies can be found, however no identification threshold data are available. This paper documents research on the observer's identification threshold for an alphanumeric resolution test object presented at various average luminance levels, contrasts, and contrast polarities. These factors affected the identification threshold in a similar way to the effects they exert on the observer's detection and recognition thresholds; the test object contrast being the most significant factor. Direct numerical comparisons between the various thresholds were not possible due to the large …

The Effect Of Targets Having Selected Line Width To Space Width Ratios On Spurious Resolution And Resolving Power, Milner Noble

Theses

Six radial targets having different line width to space width ratios were made. The effect of the ratios on the phenomena of spurious resolution and resolving power was studied on a fine grain and a coarse grain film. Spurious resolution patterns were undetectable when the dark space exceeded five times the width of the bright line. Resolving power values reached their maximum when the target contained lines that were one-fifth the width of the dark spaces between them.

Computer Program For Binary Distillation Using The Method Of Pochon-Savarit With Enthalpy Data Calculated By Lagrange Interpolation, Joseph J. Rogus

Theses

This thesis presents a Fortran Computer Program to solve binary distillation problems. The solution is obtained by the method of Pochon-Savarit which is based upon graphical use of an enthalpy-concentration diagram. The enthalpy data in this program is calculated using Lagrange interpolation. This is accomplished by utilizing the Lagrange interpolation to get values for the enthalpy of the vapor until we find that value which lies on the same line as the enthalpy of the liquid from the preceding tray and its corresponding del point.

The required input data consist of liquid-vapor equilibrium data, heat of solution data with the …

The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon

Theses

The thermodynamic properties of solutions of electrolytes may be accurately determined by the measurement of the activity of the s6lvent. when the. solute is nonvolatile, this quantity may be obtained from measurements of the lowering of the vapor pressure caused by the presence of the dissolved solute.

An experimental method has been devised to measure this effect using a semi-conventional Othmer Still. The experimental apparatus has been constructed. and evaluated. Data has been-obtained for the vapor pressure lowering of methanol due to the presence of dissolved electrolyte for five different electrolyte-methanol systems. An extrapolation technique was developed to make use …

Separation Of Isomers Via Thermal Parametric Pumping, Vincent J. D'Emidio

Theses

Continuous and semicontinuous thermal parametric pumps for separating isomers were experimentally investigated using the model system glucose-fructose-water on a cation exchange resin adsorbent. A comparison was made between the experimental data and the calculated results by a method based on an equilibrium theory. The method invokes the assumptions that a multicomponent mixture contains a series of pseudo binary systems. Each binary system consists of one of the solutes as one component and the common inert solvent as the other component. It has been shown that under certain conditions, the pump with feed at the enriched end has the capacity for …

A Preliminary Study Of The Thermodynamic Limitations Of The Nrtl/Lemf Equations, Robert Petrie

Theses

Analytical evaluations of the second and third derivatives of the molar Gibbs energy of mixing for the NRTL/LEMF equations indicate distinct zones of miscible and inmiscible prediction.

These calculations for a number of different α's have produced approximate miscibility limits for both NRTL/LEMF energy parameters and infinite dilution activity coefficients of a given system.

Transient Phenomena Of Polymer Solutions, Nikolaus Zwetkow

Theses

With the aid of a rotational viscometer, several transient phenomena were studied with different polymer solutions. In order to be acquainted with the operations of the rotational viscometer, viscosity measurements were made on polystyrene solution of a 7.14 wt. % NBS-2-35967 in a 35 - 65 mixture of aroclor and TCP, polyisobutylene (16.5% in mineral spirits), Indopol H-1900 (polyisobutylene) and 4.5% polyisobutylene in Primol 355. All these were done at a temperature of 77°F, except for Indopol H-1900 which was done at different temperatures. The results are listed in the section of tables and graphs.

Viscosity was measured with a …

A Comparison Of The Properties Of Conventional Offset Ink And Ultraviolet Ink, Vanchai Sirichana

Theses

Some of the advantageous characteristics of ultra violet ink are said to be the absence of pollution and reasonable energy consumption as well as rapid drying (curing). Little is published about physical properties or print quality. Printers require information in this regard because the reports which are presently available are not clear and lack in detail. If the printability of UV inks were equal to that of conventional offset ink, this ink would be close to an ideal ink. This work was under taken so as to compare the properties of ultraviolet ink with conventional offset ink. The inks selected …

A Quantitative Examination Of A Particular Set Of Process Inks To Determine The Effect Of Color Sequence On The Ink's Hue And Saturation Characteristics, Philip Giammatteo

Theses

The purpose of this study is to determine if there is a proper press sequence for a specific set of process inks on a specified type of paper. In the past, the literature on this subject has been of a qualitative and generalized nature. This study attempts to put the matter on a quantative basis under strict controls. A standard set of process proofing inks for web offset are chosen to be printed onto a coated type of offset paper by an IGT Printability Tester. Various techniques are devised for printing solid strips of the inks with minimum density variation …