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On The Classification Of The Solution Space Of Linear Anisotropic Elasticity, Richard Clement Carman

Dissertations

A method is developed within the framework of Synge's function-space interpretation of problems in linear elasticity which allows the consideration of solutions to problems for anisotropic media in terms of the solutions of a corresponding isotropic problem and corresponding simpler anisotropic problems. The isotropic solution and simpler anisotropic solutions establish points in each of the statically and kinematically admissible spaces for the anisotropic problem. The established points are used to define sets of vectors in the statically and kinematically admissible spaces. The linear independence of these vectors can then be determined by a pair of criteria developed in this work. …

Continuous Esterification Of Lactic Acid With N-Butyl Alcohol, Robert Dix

Dissertations

A model is proposed for the reactions occurring when an aqueous 30% lactic acid solution is contacted with a primary alcohol, normal butanol. Kinetic and equilibrium data for the esterification reactions of monomeric lactic acid and dimeric lactic acid were determined in a series of experiments using an ideal overflow back-mix reactor. The variables studied were reaction temperature and catalyst concentration.

It was determined that the significant reactions occurring within this system are the esterification of monomeric lactic acid with n-butanol and the esterification of dimeric lactic acid with n-butanol. Other reactions that may be postulated to occur within the …

A Study Of The Dynamics Of Gas Adsorption In An Air Fluidized Bed, William Charles Zalewski

Dissertations

The dynamics of gas adsorption was studied in an air fluidized bed containing activated alumina particles. The adsorption studies made with a fixed bed and in the transition region between minimum fluidization velocity and 2.0 times minimum fluidization velocity, compliment work done at higher velocities. With adsorption, particle motion controlled the overall dynamics of the fluidized bed. A different approach in applying the two phase fluidization model was necessary to satisfactorily describe unsteady state adsorption in fluidized beds. Experimental and theoretical results were compared in frequency response plots to obtain a rigorous comparison. Good agreement was obtained for flow rates …

Non-Linear Analysis Of Electrocardiogram Tracings In Detection Of Occult Coronary Artery Disease, Joseph Robert Levitt

Dissertations

The general problem of identifying significant characteristics of a system by analyzing the properties of a signal emitted by that system is common to many disciplines, biological as well as physical. In general, achievement of a satisfactory solution depends on the capability of assigning membership of candidate signals to one of a number of mutually exclusive categories:

In this study, a new technique of processing the standard electrocardiograms from human subjects has been developed. This technique employs a set of non-linear transformations which enable the assignment of electrocardiograms into one of two Mutually exclusive categories. The first category is that …

Extension And Application Of The Sedov-Berdichevskii Variational Principle, Francis X. Prendergast

Dissertations

The Sedov-Berdichevskii variational principle is extended, and this extended principle is employed in the construction of a shell theory.

The extension of the principle is accomplished by the use of Lagrangian multipliers, and a redefinition of terms in order to maintain the original generality of the principle. The Euler equations of the extended variational principle provide, in addition to those obtained in the original principle, elastic and plastic kinematic relations, and, elastic and plastic constitutive relations. Also, the Euler equations of the original principle are obtained in a physically more meaningful form. Examples are given which show how this principle …

Reliability Aspects Of Semiconductor Surface Protective Coatings, Robert Edward Mcmillan

Dissertations

This research was directed towards the occurrence and im-portance of surface leakage in reverse biased semiconductor diodes and the relation of this leakage to the reliability of a device under use conditions. As a result of this study, it is possible to predict one important leakage mechanism after such back-biased diode units have been subjected to long periods of temperature and humidity. This theory is consistent with tests of commercially available units, some of which have very slight surface leakage and others very large surface leakage.

Further, the usefulness of various possible passivating coatings is critically analyzed on the basis …

Dynamic Stress Concentrations About An Epilliptical Discontinuity In An Elastic Solid, Kenneth Roy Schroll

Dissertations

The redistribution of dynamic stresses caused by the presence of an elliptical discontinuity in an infinite isotropic homogeneous elastic solid is examined. The solutions are obtained for the special cases of the rigid immovable inclusion and the vacuous cavity inclusion, and numerical results are presented.

The solutions to the wave equations in elliptical coordinates are expressed in series of the elliptical geometry eigenfunctions. Application of the boundary conditions, vanishing displacements for the rigid immovable inclusion and vanishing stresses for the cavity inclusion, yields in each case two infinite sets of linear algebraic equations for the expansion coefficients of the series …

Oscillations In Pulse Frequency Modulated Control Systems, Warren Joseph Guy

Dissertations

This dissertation is concerned with oscillations and their stability which occur in a control system containing two nonlinearities, separated by linear elements. Specifically the nonlinearities are Integral Pulse Frequency Modulators and the linear elements are described by ordinary differential equations which are linear. The IPFM can be modelled by a quantizer with hysteresis and many other PFM laws are related to IPFM, thus the study applies to more than just IPFM alone.

Boundaries on the system parameters are identified within which free oscillation may be possible. These boundaries give sufficient conditions for stability and necessary conditions for instability. Also since …

An Analysis And Comparison Of Selected Illinois Collective Bargaining Agreements As Perceived By Superintendents, Representatives Of Teacher Groups And Prominent Negotiators, John Patrick Hayes

Dissertations

No abstract provided.

The Effects Of Level Of Education, Exposure To Psychology, And Diagnostic Nomenclature On The Psychodiagnostic Judgments Of Nonprofessionals, Everett S. Jacobson

Dissertations

No abstract provided.

Stephen Spender: Aspects Of The Quest For Reality, Marion King

Dissertations

No abstract provided.

The Effect Of Vitamin D₋B3₋S On The Incorporation Of ₋P3₋Sh-Orotic Acid Into Ribonucleic Acid Of Rat Bone, Rodger Samuel Izzo

Dissertations

No abstract provided.

The Curriculum Demonstration Project: How Effective Is It?: A Program In Quincy, Illinois For The Dropout Prone Student, Edward John. Baranowski

Dissertations

No abstract provided.

Linguistics And Language Learning: A Translation Theory, Sharon F. Mrotek Kissane

Dissertations

No abstract provided.

A Comparative Analysis Of Values, Attitudes, Opinions And Behavior Patterns Of Blacks And Whites And Chicago, James R. Neal

Dissertations

No abstract provided.

Charles Eliot: An Historical Study, John A. O'Connor

Dissertations

No abstract provided.

Simulation Of Periodic Tank Reactors, Noshir Pirojshaw Mistry

Dissertations

Normally it is assumed that the steady state mode of operation is most desirable for the design of the chemical reactor system. However it appears that this assumption may not be correct in many cases.

In the present work disturbances of various types were externally created and forced on a system comprising an isothermal continuous stirred tank reactor. The effects of these purposefully created disturbances were investigated by mathematically modelling the system and simulating it on a digital computer.

The change in reactor performance, as defined by the percentage change in the production rate from the steady state value, can …

The Distinguishing Characteristics Of High Schools With High And Low Enrollments In Physics, Thomas Earl Van Koevering

Dissertations

No abstract provided.

Concepts In Lsi Servo-Control-Electronics, Alfons Alfred Tuszynski

Dissertations

This thesis deals with the engineering aspects of control electronics. It examines modern concepts of servo-control theory in the light of recent developments in the technology of monolithic circuits. Applicational considerations are slanted towards Aerospace standards of reliability and power-consumption economy.

Conclusions drawn from the discussion of fabrication constraints and performance requirements lead to a preference for digital implementations. Yield problems on one hand and aging effects on the other greatly reduce the feasibility rating of analog arrays.

Current practice in servo-control electronics revolves around purely analog implementations, sampled-data systems and Primitive on-off arrangements. The motivation behind the status quo …

A Study Of The Cabildo In Seventeenth Century Santiago, Chile, 1609-1699, Della M. Flusche

Dissertations

No abstract provided.

An Analysis Of Electronic Data Processing Applications In Selected School Systems In Illinois, Herbert Irwin Greenwald

Dissertations

No abstract provided.

An Evaluation Of Some Predictors Of Success In College Mathematics, Florence Margaret Miller

Dissertations

No abstract provided.

A Syllogistic Approach To Attitude Change, James M. Torcivia

Dissertations

No abstract provided.

Boiling Heat Transfer In The Presence Of Electric Fields, Ronald Francis Lovenguth

Dissertations

The effects of a non-uniform, radial D.C. electric field on the natural convection and nucleate boiling regimes in saturated pool boiling and on the peak heat flux phenomenon were determined for trichlorotrifluoroethane, carbon tetrachloride, dichloromonofluoromethane and chloroform using as a heat transfer surface a 0.02 inch diameter platinum wire.

Bubble departure diameters for the nucleate boiling region were measured by photographic means as a function of the electric field intensity at the heat transfer surface.

The application of an electric field was found to have a significant effect on the natural convection mode of heat transfer and also the peak …

Viscosity-Density Correlation Of Newtonian Liquids, Melvin Leonard Druin

Dissertations

The viscosity of monatomic liquids was modeled by an equation derived from the kinetic theory of gases. Viscosities may be calculated from data on density and molecular weight of the liquid. In adapting this relationship to polyatomic liquids, a single correction factor was developed for each of five series of homologues; n-paraffins, n-1 -alkenes, n-alkylcyclohexanes, n-alkylbenzenes and n-alcohols, to account for the deviations of the calculated viscosities from those reported, extending over a one- to three-hundred degree range. The factor is a function of reduced temperature relative to the normal boiling point, T_rB. A single equation for each …

The Mechanism Of Second Breakdown In Transistors, Eugene David Fabricius

Dissertations

The purpose of this dissertation is to examine the behavior of electrons and holes in a semiconductor or diode under conditions of high current density as a function of temperature, and to relate this behavior to the phenomenon of Second Breakdown. The approach used is that of magnetohydrodynamics, the electrons and holes being treated as a plasma "gas" embedded in the dielectric of the semiconductor.

This approach is unique in the following respects:

1. This is the first attempt to explain second breakdown in terms of magnetohydrodynamics.
2. This is the first time an explanation of pinching in a solid at room …

The Generalized Virial Equation Of State, Ghanshyam R. Patel

Dissertations

A generalized three parameter virial equation of state has been developed and tested for seven pure gases having different molecular characteristics. The equation has also been tested for more than thirteen binary gas mixtures using three different mixture rules. The final equation is as follows:

Z = 1 + B(T)/V + C(T)/V² + D(T)/V³ + E(T)/V⁴ + VF(T)/e^aV + VG(T)/e^bV

The expressions for E(T), F(T), and G(T) along the critical isotherm were derived in terms of critical properties and two constants, a and b which appear in the sixth and seventh terms in the above …

Design Of Linear Control Systems With Distributed Parameter Elements By Parameter Plane Techniques, Murray Weinberg

Dissertations

This dissertation extends the application of parameter plane techniques to a number of areas. Specifically, the parameter plane technique can now be used to determine absolute stability, relative stability, and the location of roots of the closed-loop characteristic equation of systems containing both lumped and distributed parameter elements. The advantages of utilizing this technique are that results can be obtained as two system parameters are varied simultaneously and higher order systems can be treated as easily as low order ones.

Investigation of the mapping of real roots resulted in the derivation of a theorem which relates the number of real …

Noise Spectral Density As A Diagnostic Tool For Reliability Of P-N Junctions, Young Duck Kim

Dissertations

The feasibility of choosing noise-voltage spectral density as a prediction parameter for the degradation of p-n junctions has been examined both theoretically and through a series of life-tests.

Experimental facts show that the noise-voltage spectral density, S_v(w), observed in a p-n junction under the breakdown condition tends to be "white" (which contradicts the 1/f-noise theory), and S_v(w) is inversely proportional to the breakdown current (which contradicts the shot-noise theory). Furthermore, some p-n junctions display one or more multiple peaks of S_v(w) at different current levels which can not be explained by any of the …

The Radiopharmacological Evaluation Of 75 Se-Selenomethionine In Man, Moshe Ben-Porath

Dissertations

No abstract provided.