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Evaluation Of The Transition Density Function Of Carbon On Various Substrates From Kll Auger Spectrum. Application Of Auger Electron Spectroscopy To The Bulk-To-Surface Precipitation And Surface Diffusion Of Carbon On Polysrystalline Nickel, Juan F. Mojica

Doctoral Dissertations

"The time evolution of the KLL Auger spectrum of carbon was considered to be an effective tool in the l study of the diffusion process of carbon on polycrystalline nickel. Although very simple in theory, the useful application of this procedure to the desired purpose required a deeper involvement in the understanding of the Auger process.

Integration and deconvolution techniques were necessary to gain access to the information contained in the derivative mode of the Auger signal.

Part I of the dissertation describes the experimental and analytical procedures that were used in the evaluation of the transition density function of …

Effect Of Photoneutrons On Transients Of Beryllium Reflected Reactors, Safdar Ahmad Ali

Doctoral Dissertations

"An analytical model is developed to account for the photoneutron sources present in a beryllium reflector. The time-dependent, two- dimensional and three energy-group diffusion equations are written with an additional photoneutron source term. Then an approximate flux composed of two spatial shapes chosen beforehand, each having an unknown time coefficient, is inserted into time-dependent multigroup equations and the weighted residual criterion is applied. This yielded multimode kinetics equations with generalized definitions for conventional matrix parameters: generation time, reactivity, delayed neutron and delayed photoneutron fraction matrices.

Two transients are analyzed for the University of Missouri Research Reactor: simulation of rod drop …

Application Of Laser Holographic Interferometry To The Analysis Of Ground Movement Above Underground Openings, Duk-Won Park

Doctoral Dissertations

"A laser holographic interferometric technique has been recently developed and applied to research in several engineering fields. The technique has many possible applications in earth science and engineering. In this study it was shown that laser holographic ii interferometry can be used to study surface ground movements resulting from subsurface cavity collapse.

One of the most important advantages of the holographic interferometric technique is a rapid three-dimensional displacement measurement of a surface without contact or emplacement of instruments. The surface does not have to be flat or smooth allowing deflection contours to be generated on a granular surface. applied in …

Use Of Adaptive Linear Equalization And Maximum-Likelihood Sequence Estimation In Conjunction With Filtering To Improve Qpsk Communication In Intersymbol And Interchannel Interference Channels, Srinivasa H. R. Raghavan

Doctoral Dissertations

"At high data rates, bandwidth is more constraining than transmitting power. Twice the data can be transmitted in a given bandwidth by using quadrature phase-shift keyed (QPSK) modulation schemes as opposed to biphase phase-shift keyed (PSK) systems, with a corresponding factor of two increase in power required for identical bit-error-rate performance. At high data rates intersymbol interference due to media dispersion degrades receiver performance . Other degradation results from interchannel interference, co-channel interference and noise may also be present in typical situations.

Equalization is a technique by which the receiver performance in the presence of intersyrnbol interference can be improved. …

Design, Fabrication, And Application Of Uniformly Distributed Rc Networks For Use In Electronic Circuits, Michael Flynn Kavanaugh

Doctoral Dissertations

"In the design of electronic circuits, both linear and non-linear, one of the goals is the reduction of the number of elements needed to complete the design. By using distributed RC networks a reduction in the number of elements by at least 50% is usually possible. This dissertation discusses several distributed RC networks, develops detailed design procedures for each, and applies them in the design of electronic circuits.

The indefinite admittance matrix (IAM) for the DRURC (double-resistive uniformly distributed RC network) and the URC (single-resistive uniformly distributed RC network) , which have been previously derived, are used as the starting …

Development Of Helicopter Flight Path Models Utilizing Modern Control Techniques, Alfred Fermelia

Doctoral Dissertations

"The nonlinear set of equations which represents helicopter motion are linearized about a prescribed nominal state. Once the linearized system is obtained it is validated by comparing the output of the nonlinear system to that of its linearized counterpart. Having obtained a linear model, linear system theory may then be applied in order to investigate the stability and control characteristics of the aircraft.

General techniques for simulating helicopter pilot response for inclusion in a flight path simulation program have been devised. To provide the desired flight goal, a nominal flight trajectory is obtained from an existing nonlinear model. With this …

Optimizing Underground, Trackless Loading And Hauling Systems, Richard Lee Bullock

Doctoral Dissertations

"Determining the optimum system and equipment to be utilized in today's underground trackless haulage mine is a complex problem which was dealt with in this research by systems simulation. The computer program developed by the Caterpillar Tractor Company served as the starting point for simulating the equipment's capabilities to move material over a course in a prescribed time. Extensive time studies of the unsimulated events lead to structuring this program in the deterministic mode since it was felt to be more acceptable to the operating management which would eventually use the technique. Every phase of the simulation was successfully validated …

Excitation Of Source Electromagnetic Waves At Microwave Frequencies Using Optical Techniques, M. Davarpanah

Doctoral Dissertations

"The coupling efficiencies for the excitation of surface electromagnetic waves (SEW} for both the prism and the grating techniques have been studied experimentally in the microwave frequency range. The grating experiments included studies of the SEW coupling efficiencies as functions of the frequency, the angle of incidence, the grating constant, the number of grating bars, and the position of the grating bar at which the maximum radiation field of the antenna was aimed. For the prism coupling technique, the coupling efficiency was studied as functions of the angle of incidence, the aiming point of the transmitting antenna on the prism …

The Noble Gas Record Of Terrestrial And Meteoritic Samples, Edward W. Hennecke

Doctoral Dissertations

"Analyses of tellurium and xenon in a telluride ore from Kalgoorlie, Australia resulted in the following conclusions:

1. The ratio of the double beta-decay half-life of ¹²⁸Te relative to that of ¹³⁰Te is 1.6 x 10³
2. The double beta-decay half-life of ¹³⁰Te is 1.0 x 10²¹ years.
3. The measured half-lives are consistent with values predicted for a second order process of ordinary beta-decay that occurs with the emission of two neutrinos.

A study of noble gases in Thailand tektites provided the following information on the history of these objects:

1. The isotopic compositions of nonradiogenic Ne, Ar, …

Influence Of Initial Turbulence Intensity On The Heat And Moisture Transfer Through A Recirculated Air Curtain, Nguyen Quang Van

Doctoral Dissertations

"An air curtain is a directed jet of air separating a controlled space from an environment of different temperature and humidity. This investigation describes the development and verification of an eddy viscosity model which accounts for the influence of the initial turbulence intensity on the transfer of heat and moisture across a recirculated air curtain. The control of the turbulence intensity at the nozzle exit of an air curtain permits control of heat and moisture transfer and therefore the energy required to operate the air curtain.

Both theoretical and experimental studies were made of the recirculated air curtain. An explicit …

Mixed Nonderivative Algorithms For Unconstrained Optimization, Roger Ellis Lessman

Doctoral Dissertations

"A general technique is developed to restart nonderivative algorithms in unconstrained optimization. Application of the technique is shown to result in mixed algorithms which are considerably more robust than their component procedures. A general mixed algorithm is developed and its convergence is demonstrated. A uniform computational comparison is given for the new mixed algorithms and for a collection of procedures from the literature"--Abstract, page ii.

A Heuristic Algorithm For The Multi-Terminal Vehicle Dispatch Problem Using The Modified Sweep Algorithm, Jerry George Johnson

Doctoral Dissertations

"A heuristic algorithm is developed for solving the multi-terminal vehicle dispatch problem. The demand points are first assigned to terminals using a scheme that minimizes the cost of each assignment. Single-terminal vehicle dispatch problems are then solved at each terminal using a heuristic procedure, called the Sweep Algorithm. A sequence of trial reassignments are then attempted in order to obtain further improvements in the overall solution. Eleven multi-terminal vehicle dispatch problems are presented and their solutions, derived by this procedure, are given.

Several changes are also proposed for the Sweep Algorithm in order to improve the solutions obtained and to …

A Study Of Some Life Testing Distributions, Robert Marvin Smith

Doctoral Dissertations

"This dissertation is presented in publication form and consists of three articles. The first article considers a new life-testing distribution which has the property of possessing a failure rate function which can be U-shaped or exponentially increasing depending on the value of the shape parameter. In addition, this article considers generalized least squares type estimators for location-scale distributions, then uses these estimators in the analysis of the exponential-power distribution. Tables are provided for which inferences on the location and scale parameters and on the reliability can be obtained. The second article gives relationships between a goodness-of-fit statistic based on a …

Bit Penetration Into Rock - A Finite Element Study, Jaw-Kuang Wang

Doctoral Dissertations

"A finite element approach has been developed to simulate bit penetration from bit-rock interaction to chip formation. A mathematical rock failure model, based on a review of the existing literature on rock tests, has been proposed to represent post-failure rock behavior and applied in the penetration simulations. The finite element program has been developed for two dimensional plane strain problems with non-linear material properties, geometrical nonlinearities and fracture. An anisotropic element as well as variable stiffness and stress release methods have been used. An iteration method, using an incremental approach, has been applied for continuous penetration and modifications of material …

Classification Of Surficial Materials, James Hadley Williams

Doctoral Dissertations

"A surficial materials classification system has been designed to fit the needs of a geologist in mapping and classifying surficial materials. The system developed in this study is intended primarily for analysis of surficial materials where time-stratigraphic markers are not applicable or recognized. Primary classification is based on fabric and mode of origin supplemented by data on engineering and pedologic properties.

Several types of classification systems presently exist for use in soil investigations. Only three of these systems have found widespread acceptance, two serving the engineering profession and the other the needs of the soil scientist. These systems are not …

Interrelationship Of Energetic Particles, Plasma And Magnetic Fields In The Inner Heliosphere, Jerome Theodore Nolte

Doctoral Dissertations

No abstract provided.

The Eminence Of American Psychologists, Richard A. Bagg

Doctoral Dissertations

No abstract provided.

The Ecology Of Community Integration And The Incidence Of Mental Disorder: An Analytical Study, Bradford Sears Wild

Doctoral Dissertations

No abstract provided.

The Identity-Equivalence Decalage In Piaget's Conservation Problems, Michael John Chiseri

Doctoral Dissertations

No abstract provided.

Thermomechanics Of Anisotropic Heterogeneous Materials With Particular Application To Wood During The Drying Process, Yusuf Altan Meric

Doctoral Dissertations

No abstract provided.

Interaction Of Sound And Turbulence With Particular Application To The Scattering Of Sound From A Turbulent Wake, Moses Robinson Swift

Doctoral Dissertations

No abstract provided.

Attitude Agreement, Task Competence, Information Search And The Choice Of Work Partners In The Attraction-Similarity Paradigm, Alan Lee Carsrud

Doctoral Dissertations

No abstract provided.

An Approximate Solution To The Moving Boundary Problem Associated With The Freezing And Melting Of Lake Ice, Stephen Danforth Foss

Doctoral Dissertations

No abstract provided.

Phytoplankton Primary-Productivity In Massachusetts Bay, Jon Irving Parker

Doctoral Dissertations

No abstract provided.

H-Structures On Sp(2), Su(4) And Related Spaces, Curtis Paul Murley

Doctoral Dissertations

No abstract provided.

Submersible Maneuvering And Control, Gregory John Schoenau

Doctoral Dissertations

No abstract provided.

Foraging Strategies And Predation Effects Of Asterias Rubens And Nucella Lapillus, John Henry Annala

Doctoral Dissertations

No abstract provided.

Solvent Effects Upon Substitution Reactions Of Metal Complexes, Dagoberto Pacheco Alvarez

Doctoral Dissertations

No abstract provided.

The Chemical And Electrochemical Oxidative Decarboxylation Of Methyliminodiacetic Acid In Acid Media, Rita Kathleen Hessley

Doctoral Dissertations

"Methyliminodiacetic acid (MIDA) is oxidized with cerium. (IV) in both perchloric and sulfuric acids to give sarcosine, formaldehyde, and carbon dioxide"--Abstract, page 2.

Cross Sections For Photoionization Of The 6²P-Fine Structure Levels Of Cesium, John Daniel Jones

Doctoral Dissertations

"The cross sections for photoionization of excited cesium from the 6²P_3/2- and 6²P_1/2-fine structure levels have been measured using a triple crossed-beam apparatus. Two photon beams, one for excitation and one for ionization, impinge upon an atomic beam and produce ions at the point of intersection. The relative cross section is determined from a knowledge of the ion count rate and the relative photon flux of the ionization light. The results are normalized to available theoretical calculations and compared with recombination measurements in cesium plasmas. The present cross sections are found to decrease with …