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Analysis Of The Traveling-Wave Transistor, Vernon Ray Stanley
Analysis Of The Traveling-Wave Transistor, Vernon Ray Stanley
Doctoral Dissertations
"Transmission lines containing independent and dependent distributed sources are considered and the transfer matrices of various active distributed lines are derived. A method is discussed by which a lossy line can be made lossless by the appropriate choice of distributed sources. A steady-state analysis of the uniform traveling wave transistor is given. Considering the device as an active four port network, the transfer matrix is found in closed form and the power gain, output voltage, and input impedance are found. A computer program is written and the frequency response is given for various values of line parameters and terminations. Finally, …
Characterizing Topologies By Continuous Selfmaps, Derald David Rothmann
Characterizing Topologies By Continuous Selfmaps, Derald David Rothmann
Doctoral Dissertations
"Various topological spaces are examined in an effort to describe topological spaces from a knowledge of their class of continuous selfmaps or their class of autohomeomorphisms. Relationships between topologies and their continuous selfmaps are considered. Several examples of topological spaces are given and their corresponding classes of continuous selfmaps are described completely. The problem, given a set X and a topology U when does there exist a topology V either weaker or stronger than U such that the class of continuous selfmaps of (X,V) contains the class of continuous selfmaps of (X,U), is considered. M* and S** spaces are defined …
A Finite Element Method For Geometrically Nonlinear Large Displacement Problems In Thin, Elastic Plates And Shells, Ronald August Melliere
A Finite Element Method For Geometrically Nonlinear Large Displacement Problems In Thin, Elastic Plates And Shells, Ronald August Melliere
Doctoral Dissertations
"A finite element method is presented for geometrically nonlinear large displacement problems in thin, elastic plates and shells of arbitrary shape and boundary conditions subject to externally applied concentrated or distributed loading. The initially flat plate or curved shell is idealized as an assemblage of flat, triangular plate, finite elements representing both membrane and flexural properties. The 'geometrical' stiffness of the resulting eighteen degree-of-freedom triangular element is derived from a purely geometrical standpoint. This stiffness in conjunction with the standard small displacement 'elastic' stiffness is used in the linear-incremental approach to obtain numerical solutions to the large displacement problem. Only …
A Method For Determining Transient Stability In Power Systems, Charles A. Gross
A Method For Determining Transient Stability In Power Systems, Charles A. Gross
Doctoral Dissertations
"Given a three phase ac power system consisting of synchronous alternators interconnected by transmission lines and other items of electrical transmission equipment, a method is presented which determines the stability of the system when subjected to a three phase symmetrical fault, and to the subsequent clearing of the fault. It is inherent in the method that an estimation of system stability, assuming an instantaneous clearing of the fault, is available. The critical clearing time is therefore determined. The effect of a speed control loop on the system's largest machine is investigated. The method is applied to two, three, four, and …
Models For The Pn Diode And The Npn And Pnp Transistor For Use In Computer Aided Design And Analysis Programs, Glenn Ronald Case
Models For The Pn Diode And The Npn And Pnp Transistor For Use In Computer Aided Design And Analysis Programs, Glenn Ronald Case
Doctoral Dissertations
"This work is concerned with the problem of developing suitable mathematical representations for the pn junction diode and npn and pnp transistors for use in computer aided design and analysis programs. The Ebers-Moll model as used in the Net-1 program has been considerably improved, particularly regarding base resistance prediction, prediction of high forward current behavior, and the addition of reverse breakdown terms. The resulting models show substantial improvement in representation of d-c and transient characteristics. Some improvement in a-c characteristics has also been obtained. Methods of obtaining parameters for the new model and several of the present models, given measured …
Numerical Inversion Of The Laplace Transformation And The Solution Of The Viscoelastic Wave Equations, Abbas Ali Daneshy
Numerical Inversion Of The Laplace Transformation And The Solution Of The Viscoelastic Wave Equations, Abbas Ali Daneshy
Doctoral Dissertations
"In the numerical inversion of Laplace transform two general techniques of inversion are analyzed; a study of the procedures based on an expansion of f̄(s) by a polynomial in 1/s (Salzer's method) provides accurate results for certain ranges of t. A curvature criterion for the selection of the range of points for polynomial interpolation, and a geometric distribution in this interval markedly improves the range and the degree of accuracy of inversion. The results may be further improved by multiplying f̄(s) by 1/s of 1/s². Other procedures are based on approximation of f̄(t). This investigation includes a general review of …
Noble Gases: A Record Of The Early Solar System, E. C. Alexander
Noble Gases: A Record Of The Early Solar System, E. C. Alexander
Doctoral Dissertations
"Analyses of the noble gases in samples of iron meteorites are presented which indicate the following: 1. The inclusions of iron meteorites contain noble gases with a wide range of isotopic compositions. 2. The noble gas concentration and isotopic anomalies arc often grossly inhomogeneously distributed within a given inclusion and vary from inclusion to inclusion in a meteorite. 3. Silicate inclusions appear to be the most promising samples for I-Xe and Pu-Xe dating. 4. Graphite and troilite in addition to the silicate inclusion contain significant radiogenic ¹²⁹Xe anomalies. 5. The total I-Xe (and in the case of Toluca silicates total …
Signal Distortion In A Regenerative Frequency Divider, Carl Ray Ryan
Signal Distortion In A Regenerative Frequency Divider, Carl Ray Ryan
Doctoral Dissertations
"A regenerative frequency divider can be constructed with one integrated circuit and a single-pole tuned circuit. The divider can be used as a means for reducing the modulation index of either deterministic or random signals. This reduction in modulation index can simplify many signal processing schemes. This technique can be used up to S-band frequencies. The mathematical model of the regenerative frequency divider corresponds very closely to that of a first order Phase Locked Loop (PLL). The loop gain is determined in part by the nonlinear element used in the feedback loop. The loop gain is also proportional to the …
Statistical Inferences For The Cauchy Distribution Based On Maximum Likelihood Estimators, Gerald Nicholas Haas
Statistical Inferences For The Cauchy Distribution Based On Maximum Likelihood Estimators, Gerald Nicholas Haas
Doctoral Dissertations
"Various estimators of the location and scale parameters in the Cauchy distribution are investigated, and the superiority of the maximum likelihood estimators is established. Tables based on maximum likelihood estimators are presented for use in making statistical inferences for the Cauchy distribution. Those areas considered include confidence intervals, tests of hypothesis, power of the tests, and tolerance intervals. Both one- and two-sample problems are considered. Tables for testing the hypothesis of whether a sample came from a normal distribution or a Cauchy distribution are presented. The problems encountered in finding maximum likelihood estimators for the Cauchy parameters are discussed, and …
The Statistics Of Finite, One Dimensional Lattice Fluids, John Roger Glaese
The Statistics Of Finite, One Dimensional Lattice Fluids, John Roger Glaese
Doctoral Dissertations
"A one dimensional lattice fluid in which particles are allowed to assume only discrete positions is proposed. Particles are free to move from one lattice site to another interacting through a variety of potentials, including the Lennard-Jones type. The model allows the partition function to be evaluated as a discrete sum over the allowable configurations. Both the canonical ensemble and grand ensemble are treated by computer and a third, the pressure ensemble, is considered and shown to be useful in the theoretical treatment of lattice systems. The thermodynamic behavior of various systems is investigated in both the canonical and grand …
Vapor Phase Clustering Model For Water, Richard W. Bolander
Vapor Phase Clustering Model For Water, Richard W. Bolander
Doctoral Dissertations
"Although nucleation phenomena are among the most widespread of all naturally occurring phenomena, even the simplest of nucleation processes, homogeneous nucleation, is poorly understood, particularly the homogeneous nucleation of liquid droplets from water vapor. Homogeneous nucleation involves only molecules of a single substance and does not include the complicating effects due to a substrate or piece of foreign matter. The semiphenomenological liquid drop theories developed nearly three decades ago differ in relatively minor details, with the crucial element of the theory being the derivation of the free energy of formation of the clusters. The clusters are viewed as well-defined incompressible …
Longitudinal Optical Phonon-Plasmon Coupling In Ionic Semiconductors, Thomas Joseph Mcmahon
Longitudinal Optical Phonon-Plasmon Coupling In Ionic Semiconductors, Thomas Joseph Mcmahon
Doctoral Dissertations
"The coupling of free carriers and lattice vibrational modes is studied in CdS and InSb by room temperature far infrared reflectance measurements. When the free carrier concentration is such that the plasma frequency is at or near the longitudinal optical mode frequency it is shown that while the transverse modes remain fixed, the longitudinal modes mix with the plasma mode and are shifted in a manner similar to that described by Varga in 1965. Using the dielectric function for the coupled system permits the determination of electron effective masses by reflectance measurements with lattice effects excluded. This method allows one …
I A Study Of The Basicities Of Some Aryl Methyl Sulfoxides Ii A Study Of The Hydrolysis Of Arenesulfinamides In Basic Aqueous Ethanol, Joseph Brian Biasotti
I A Study Of The Basicities Of Some Aryl Methyl Sulfoxides Ii A Study Of The Hydrolysis Of Arenesulfinamides In Basic Aqueous Ethanol, Joseph Brian Biasotti
Doctoral Dissertations
No abstract provided.
Purification And Characterization Of Staphylococcal Nuclease, David Gordon Stuart
Purification And Characterization Of Staphylococcal Nuclease, David Gordon Stuart
Doctoral Dissertations
No abstract provided.
The Hot-Atom Chemistry Of Sulfur(35) Produced By The Chlorine-35(Neutron,Proton)Sulfur-35 Reaction In Mixed Crystals Of Potassium Chloride And Potassium Bromide, John Robert Hobbs
The Hot-Atom Chemistry Of Sulfur(35) Produced By The Chlorine-35(Neutron,Proton)Sulfur-35 Reaction In Mixed Crystals Of Potassium Chloride And Potassium Bromide, John Robert Hobbs
Doctoral Dissertations
No abstract provided.
A Conformational Study Of Various 3- And 4-Piperidinols, David Harold Mcmahon
A Conformational Study Of Various 3- And 4-Piperidinols, David Harold Mcmahon
Doctoral Dissertations
No abstract provided.
Seasonal Variation Of Aliphatic And Phenolic Acids And The Relationship Between Titratable Acidity And Percentages Of Calcium, Magnesium And Potassium In The Leaves Of Selected Mcintosh Apple Clones, John Chrysostom Mugwanya Ddungu
Seasonal Variation Of Aliphatic And Phenolic Acids And The Relationship Between Titratable Acidity And Percentages Of Calcium, Magnesium And Potassium In The Leaves Of Selected Mcintosh Apple Clones, John Chrysostom Mugwanya Ddungu
Doctoral Dissertations
No abstract provided.
The Reactions Of Organometallic Reagents With Pyridinium Salts, Edward White V.
The Reactions Of Organometallic Reagents With Pyridinium Salts, Edward White V.
Doctoral Dissertations
No abstract provided.
The Extension Of A Locally Compact Local Group To A Global Group, David Warren Cohen
The Extension Of A Locally Compact Local Group To A Global Group, David Warren Cohen
Doctoral Dissertations
No abstract provided.
Measurement Of Ionospheric Absorption By The Cosmic Radio Noise Method, J Ronald Earhart
Measurement Of Ionospheric Absorption By The Cosmic Radio Noise Method, J Ronald Earhart
Doctoral Dissertations
No abstract provided.
I Preparation Of N-Sulfonylsulfilimines Via Cycloaddition Reactions Of N-Sulfonyl Isothiocyanates And N-Sulfonyl Phosphinimines With Sufoxides Ii Attempt At Preparing (Methylsulfinyl)Alkyl Isothiocyanates Via Optically Active Methanesulfinate Esters, John Butler O'Brien
Doctoral Dissertations
No abstract provided.
The Damage Assessment Of Thermally Shocked High Density, High Purity Aluminum Oxide, John H. Ainsworth
The Damage Assessment Of Thermally Shocked High Density, High Purity Aluminum Oxide, John H. Ainsworth
Doctoral Dissertations
"The traditional approach to thermal shock testing in brittle materials has been to determine the temperature difference required to nucleate cracks in these materials. Recent work has indicated that the degree of damage after crack nucleation should be an additional consideration. The degree of damage resulting from cooling thermal shocks has been the primary consideration of the present work. Test specimens of two geometries: long, solid rods and short, solid cylinders were quenched from selected temperatures into ice water. The degree of damage was determined through strength measurements and sonic damping analysis. Initial damage occurred at a temperature difference above …
Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe
Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe
Doctoral Dissertations
"The circulating drop mass transport model based on Hadamard's dispersed phase stream function was solved numerically to account for a solute diffusing into a droplet and undergoing a first order irreversible reaction with the drop medium for the case where the continuous phase resistance to solute transport is negligible ... Experimental data were obtained for a system which consisted of 2-chloro-2-methylpropane (t-butyl chloride) diffusing from a benzene continuous phase into falling water droplets and undergoing a first order irreversible reaction with the water droplets ... The experimental solute transport rates were a factor of 7 to 10 greater than those …
Hrva - A Velocity Analysis Technique For Seismic Data, John Charles Robinson
Hrva - A Velocity Analysis Technique For Seismic Data, John Charles Robinson
Doctoral Dissertations
"A High-Resolution Velocity Analysis (HRVA) has been developed for the determination of the root-mean-square subsurface-velocity energy spectrum from gated seismic data which has been normal-moveout corrected. All calculations are performed in the frequency-space or frequency-wavenumber domain; seismic gates are transformed from the time-space domain via the Fast Fourier Transform algorithm. HRVA is not restricted to the investigation of apparent horizontal velocities which have associated stepout values that are integral multiples of the time sampling interval, as are the existing correlation techniques. The technique liberally exploits the inexistence of significant energy in the higher frequency harmonies of seismic data, resulting in …
An Experimental Determination Of The Homogeneous Nucleation Rate Of Water Vapor In Argon And Helium, Louis Benton Allen
An Experimental Determination Of The Homogeneous Nucleation Rate Of Water Vapor In Argon And Helium, Louis Benton Allen
Doctoral Dissertations
"An expansion type cloud chamber was used to measure the nucleation rate of water vapor in an atmosphere of helium and argon. A careful study was made of the thermodynamic characteristics during the expansion so that the nucleation data could be interpreted with reasonable accuracy and consistency. A fine wire thermocouple was used to measure the gas temperature during the course of an isentropic expansion in the dry chamber. When the finite heat capacity of the thermocouple is accounted for, it is found that there is almost perfect agreement with the temperature calculated from the equation of state and the …
Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman
Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman
Doctoral Dissertations
"For the most part, solutions to the problems of making inferences about the parameters in the Weibull distribution have been limited to providing simple estimators of the parameters. Little has been known about the properties of the estimators. In this paper the small and moderate sample size properties of the maximum likelihood estimators are studied and their superiority is established. The problem of making further inferences which are based on the maximum likelihood estimates of the parameters is then considered. The inferences that are presented can be divided into those based on a single sample and those based on two …
Investigation By Neutron Diffraction Utilizing White Neutron Radiation, Arlen Ray Schade
Investigation By Neutron Diffraction Utilizing White Neutron Radiation, Arlen Ray Schade
Doctoral Dissertations
"The most probable reactor core neutron velocity was determined by analysis of data obtained from single crystals of copper and lithium fluoride. Derivation of the relationship between the maximum in experimental count rate and the most probable velocity, an error analysis of the method, and the computer routine are given for the method used to obtain the most probable velocity. The most probable velocity was used to index the maxwellian distributions from polycrystalline materials. Investigations were done with white neutron radiation of various silicon steel samples of different preferred orientation. A method is described by which the preferred orientation of …
Decomposition Of Cr(Oh)₃ To Form Active Cr₂C₃, Timothy A. Clancy
Decomposition Of Cr(Oh)₃ To Form Active Cr₂C₃, Timothy A. Clancy
Doctoral Dissertations
"This study was concerned with the sinterability of Cr₂C₃ powders produced by the calcination of a Cr(OH)₃ gel. The decomposition of the gel was investigated by thermogravimetric analysis, X-ray analysis and microscopic examination. Comparison was made between the size of crystallites as determined by X-ray line broadening and the size of aggregated particles as determined by independent means. These lineal measurements were compared to surface area measurements on the calcined powders. The degree of sinterability was judged from the density measurements on Cr₂C₃ pellets fired under air, oxygen and nitrogen atmospheres. Energies of activation of 25 and 20 kilocalories per …
The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett
The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett
Doctoral Dissertations
"The measurement of the lifetime of the metastable 6²P₃/₂ state of thallium is discussed. Measurement of time varying optical absorption by time sampling techniques is explained for the study of the decay of the metastable atom concentration following a pulsed radio frequency discharge. The decay of the thallium radiation from optically allowed states terminating on the metastable state is measured at nine different thallium densities in the afterglow of the discharge. This radiation repopulates the metastable state and is displayed on an oscilloscope. The metastable lifetime is measured as a function of the thallium density at three different r-f power …
Deuterium Isotope Effects On The Solvolysis Rates Of Cyclopentyl Brosylates And Tosylates, Jimmie D. Christen
Deuterium Isotope Effects On The Solvolysis Rates Of Cyclopentyl Brosylates And Tosylates, Jimmie D. Christen
Doctoral Dissertations
"The brosylates and tosylates of cyclopentanol and its 1-d₁, c̲i̲s̲-2-d₁, t̲r̲a̲n̲s̲-2-d₁, and 2,2,5,5-d₄ analogs have been synthesized and their solvolysis rates measured at 25° in 70% vol. ethanol-water. The solvoylsis reactions were monitored by a conductance method. The isotope effects, kH/kD, observed for the brosylates and tosylates of each of the isotopically substituted cyclopentyl alcohols are as follows: 1-d₁-brosylate (1.1869) and 1-3₁-tosylate (1l1836); c̲i̲s̲-2-d₁-brosylate (1.1533) and c̲i̲s̲-2-3₁-tosylate (1.1577); t̲r̲a̲n̲s̲-2-d₁-brosylate (1.1803) and t̲r̲a̲n̲s̲-2-d₁-tosylate (1.1765); 2,2,5,5-d₄-brosylate (1.8881) and 2,2,5,5-d₄-tosylate (1.8863). The closeness in magnitude of the isotope effects for the c̲i̲s̲- and t̲r̲a̲n̲s̲-isomers is important in that it …