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Impulse Response Of Rc Exponential Lines, Oscar Gojon

Masters Theses

"This thesis presents an application of the analysis of the n-wire exponential line to the case of the 3-wire RC exponential line terminated in its characteristic impedance, and to the 2-wire exponential line with open and short circuit terminations. These lines are excited with Δ-function voltage generators, and the corresponding impulse responses are obtained"--Abstract, Page ii.

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 …

Recombination Statistics For The Neutron-Induced Base Current Component, Ming-Chwan Chow

Doctoral Dissertations

"This paper presents a derivation of the recombination statistical model for the neutron-induced base current component. The derivation was based on the assumptions: 1) the current equation for the induced current component developed by Goben is valid; 2) the Shockley-Read-Hall statistics for holes and electrons are applicable; and 3) the recombination statistics derived by Sah, Noyce and Shockley, for sites in the bulk space-charge region are valid. Several examples were presented to emphasize accuracy of this derived model for predictions. This paper shows that the recombination process may be described by a mathematical model, recombination statistics which depend on the …

Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe

Doctoral Dissertations

"Surface self-diffusion coefficients have been measured by a radioactive tracer method over the temperature range 614⁰ to 840⁰C on nickel (111) surfaces characterized by LEED. Previously unrecognized tracer evaporation during surface diffusion resulted in restricted spreading of the tracer at higher temperatures. A theoretical treatment of the tracer evaporation phenomenon is presented and subsequently used in the analysis of the data. The temperature dependence of the surface self-diffusion coefficient (D_s) for nickel (111) can be represented, over the experimental temperature range, by a single Arrhenius type relationship...Arguments are presented to justify an adatom surface diffusion mechanism which is …

Design Of A Sequential Detector, Scott William Abel

Masters Theses

"The communication engineer has in the past treated the detection problem from a limited point of view. Detectors have been designed to reach a decision based on a specified number of samples. This approach has proved valuable, but it offers no provisions for an early decision if a conclusion becomes obvious early in the sampling. Neither is there an opportunity for additional sampling if necessary to reach a definite conclusion, because of these limitations it is desirable to find more general detectors. This study looks at a specific statistics (the sign test) and designs a sequential detector to utilize this …

Semiempirical Determination Of The Differential Fast Flux Spectrum For U-235 Fission With Water Moderator, Henry Anthony Till

Masters Theses

"The differential fast flux spectrum of the UMR Pool Research and Training Reactor core was determined by simultaneous activations of threshold foil detectors by neutron-nucleon reactions. This represents one phase of the composite neutron environment at two sample irradiation locations and the center of a fuel element during a power operation of 200 Kw (th). To accomplish this measurement a semiempirical least-squares approximation fitting activation date to a theoretical Cranberg U-wet fission spectrum was applied. This is a technique designed specifically for water moderated systems and takes into consideration both virgin and down-scatter neutrons. Gamma decay photopeaks were reduced using …

Shear Strength Behavior In Silts And Clay Mixtures, Alan T. Jackson

Masters Theses

"A series of consolidated undrained triaxial tests with pore pressure measurements were performed on laboratory sedimented samples having various known silt to clay content ratios. The clay used was commercial grundite clay from Goose Lake, Illinois, and the silt used was extracted from Lebanon Silt Loam from Rolla, Missouri. Silt was mixed with clay in the following percentages by weight: 0%, 20%, 40%, 50%, and 80%. Results indicate an increasing angle of internal friction with an increase in silt content. The unconfined compressive strength of the samples remained constant, as would be expected in a clay, with increasing silt content …

Pressure Welding Of Continuously Cast Nodular Iron, Gerald W. Wille

Masters Theses

"The objective of this study was to determine the feasibility of using pressure welding as a joining technique for swaged nodular iron.

Test pressure welds were produced with swaged continuous cast nodular iron at temperatures between 1750⁰F and 2050⁰F with welding pressures between 15,900 psi and 51,400 psi using an induction coil to heat the weld zone.

Pressure welds of greater strength than the as-received nodular iron were produced by swaging the material before welding. The optimum welding parameters were a temperature of 2050⁰F with a welding pressure of 46,700 psi.

On the basis of these tests it is concluded …

Synchronization Of Pulse Code Modulation Telemetry, Lawrence J. Mueller

Masters Theses

"Pulse Code Modulation (PCM) is one of the most widely utilized radio telemetry techniques for the recovery of test data from aerospace vehicles. Synchronization of the receiver with the transmitted data is perhaps the prime requisite of a PCM telemetry system. In this paper the frame synchronization process is analyzed by developing equations which define the three modes of synchronizer operation (SEARCH, VERIFY, and LOCK) in terms of the relative probabilities of operation. The criteria employed to optimize the synchronization process are the mean time to acquire true synchronization, the probability of true synchronization after verification of the synchronization decision, …

A Computer Adaption Of Plastic Analysis For Rigid Frames, Gerald Duane Galloway

Masters Theses

"A computer program for the plastic analysis of rigid frames is presented. The program is based on the virtual work method of plastic analysis. The great number of failure mechanisms that must be considered in any virtual work analysis are given in Appendix C. The use of the program as a design aid is also discussed. A check for the virtual work program is also presented. The check is based on the method of inequalities as initially presented by Symonds and Neal"--Abstract, page ii.

The Inert Gas Effect On The Rate Of Evaporation Of Zinc And Cadmium, Chu Sheng Wu

Masters Theses

"An experimental study has been made to investigate the effect of argon and helium on the rate of evaporation of zinc and cadmium under one atmosphere pressure at temperatures ranging from 500⁰C to 850⁰C. The experimental results were compared with the maximum rates calculated using the effusion formula as well as with values obtained using three different types of equations based on kinetic theory, diffusion theory, and empirical data. The rate of evaporation in this study appeared to be diffusion controlled. Equations have been derived for expressing the rate of evaporation of zinc and cadmium in both argon and helium …

Evaluation Of Methods For Analysis Of Multi-Degree-Of-Freedom Systems With Damping, Brijgopal R. Mohta

Masters Theses

"A general review of various methods for studying the behavior of linear lumped parameter systems with viscous damping is presented. Five methods are discussed. These are: (1) Normal Mode Technique (2) Ho's Method (3) Impedance Method (4) Graphical Technique (5) A Method for Reducing Degrees-of-freedom. For solution of vibration problems by the Normal Mode Technique, the systems are classified as (1) classically damped or (2) non-classically damped. It is shown that the classically damped systems are relatively easy to solve. For non-classically damped systems, the method proposed by K. A. Foss has been employed. This method is quite complex, but …

Measurement Of Demagnetizing Factor Of Ring-Core, Subhashchandra Chimanlal Patel

Masters Theses

"A method has been presented to measure the demagnetizing factor of ring-cores. First the incremental apparent permeability and the incremental true permeability were measured at different degrees of saturation and then the demagnetizing factor was determined from those results. The cores used were tape would ring-cores of mean length of 8.0 cm. The method was found suitable for cores with 1/4 mil or thicker tape, but was in question for the 1/8 mil tape core tested"--Abstract, page ii.

Estimation Of Film Boiling Heat Transfer Coefficients For Cylindrical Heaters In Corresponding States Fluids, Gary Joseph Capone

Masters Theses

"An investigation of film boiling heat transfer was made with cylindrical heaters. The (0.75" O.D.) gold plated, copper heaters were positioned horizontally in pools of liquid argon, nitrogen, and carbon monoxide. A correlation for film boiling corresponding states fluids is derived and discussed. The correlation is a least squares fit of three variables: the diameter of the cylindrical heater, the reduced pressure of the system, and the temperature difference between the heater surface and the saturated pool"--Abstract, page iii.

Analytical And Experimental Methods For Determining The Properties Of Materials At Very High Rates Of Loading, A. G. Behring

Masters Theses

"In the following report, some of the properties of ALCOA 7075 T651 aluminum, when subjected to high rates of loading, are experimentally investigated by impacting two rods of the material longitudinally. One rod is accelerated to a uniform velocity with an air gun launcher. The stationary second rod is instrumented with strain gages on its lateral surface in order to determine the strain-time history following impact. A detailed description of the experimental equipment is included. Simple, one-dimensional theory is used to determine the dynamic, elastic modulus of the test material under the impact condition. Several observations regarding the behavior of …

The Design Of A Molten Fueled, Vortex Reactor, For Use As A Rocket Propulsion Device, Robert Philip Schmitt

Masters Theses

"The purpose of this investigation is to design a nuclear reactor which can be used as a rocket propulsion device. The reactor investigated is fueled with a molten uranium-bismuth alloy and utilizes a two phase vortex flow principle. Hydrogen is employed as a coolant and rocket propellant. The hydrogen is heated directly by the fuel thus eliminating the need for heat exchangers. The major part of the investigation consists of a two group neutron diffusion study to show the operational feasibility of this type of reactor and to obtain an optimum design. the study shows that this type of reactor …

Training Needs For Metal Tradesmen In Iowa, Harlan E. Giese

Dissertations and Theses @ UNI

This study was undertaken to assist area schools and the State Board of Public Instruction by identifying the industrial training needs for semi-skilled and skilled metal tradesmen.

One of the problems confronting the administrators of the area community colleges, vocational schools, and high schools in Iowa is that of identifying the industrial training needs of manufacturers and business firms in the state. This need identification is necessary so that students trained in occupational curricula in the area-community colleges and vocational schools, and local high schools will find jobs available in their field of specialization when they graduate.

The area schools …

Interstitial Solute Trapping In Irradiated And Quenched Iron, M. (Manfred) Wuttig, J. T. Stanley, H. K. Birnbaum

Materials Science and Engineering Faculty Research & Creative Works

The interaction of interstitial carbon and nitrogen solutes with defects produced by low temperature neutron irradiation and by quenching was studied in high purity and Ferrovac E iron. Magnetic Dis accommodation techniques were applied to determine the interstitial solute content after irradiation and upon annealing. Doses of about 1017 neutrons/cm2 caused the trapping of about 20 ppm (atomic) interstitial solutes at 65 (carbon) and 40°C (nitrogen). Trapping of carbon in a Ferrovac E iron alloy occurred during a fast quench from 880°C. After trapping, the interstitial solutes reappeared in solid solution at 300 (carbon, neutron irradiation), 200 (nitrogen, neutron irradiation), …

Current Density-Anodic Potential Curves Of Single Crystal Gaas At Low Currents In Koh, Martin E. Straumanis, J. P. Krumme, William Joseph James

Materials Science and Engineering Faculty Research & Creative Works

Single p-type, GaAs crystals of high purity, Zn doped, were used to determine whether or not the inverse octahedral {111} faces show potential differences and various rates of anodic dissolution. The Ga{111}, As{111}, {110}, and {100} faces, were polished, etched, and etch-polished with concentrated H₂SO₄ + H₂O₂, and immersed in IN KOH. The Ga{111} faces were found to be the most noble with respect to rest and anodic dissolution potentials. The potential difference between the inverse {111} faces was as large as 0.14v for the rest and 0.123v for the dissolution potentials. The …

A Metallographic Study Of Solidification And Segregation In Cast Aluminum-Uranium Alloys, Bruce L. Bramfitt, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

The micromorphology and type of segregation in vacuum-cast ingots of aluminum-uranium alloys, ranging from 5 to 30 weight percent, were studied. The microstructural characteristics are similar to those of aluminum-silicon alloys of the same composition range, except that the aluminum-uranium eutectic was identified as having "chevron" and "rhombic spiral" types of morphology. © 1968.

Cutting Nbs Budget, Norbert J. Kreidl

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

A Direct Method Of Measuring Stray Load Loss In Dc Machines, Kanaiyalal R. Shah, George Mcpherson

Electrical and Computer Engineering Faculty Research & Creative Works

Stray load loss in dc machines is denned as the difference between the actual loss under load and the well-recognized loss. This paper describes a simple, reliable, and direct method of measuring this loss by means of a proposed short-circuit test with a correction factor for uncompensated-type dc machines. It also describes the sources and components of stray load losses as they occur under short-circuit test. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.

A Simple Design Algorithm For Synthesis Of Multilevel Combinational Networks, James H. Tracey

Electrical and Computer Engineering Faculty Research & Creative Works

An algorithm is presented for the synthesis of combinational networks with a constrained arrangement of ANDS, ORS, NANDS, NORS, and inverters. The algorithm is easily presented to students in an introductory logic design course and has considerable application in modern practical logic design. Many texts available for a first course in logic design give very limited practical guidance for synthesis of networks under constraints outlined here. It is suggested that the algorithm presented here be furnished as supplementary material in the introductory course. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.

Recombination Statistics For Neutron Bombarded Silicon Transistors, M. C. Chow, J. L. Azarewiczt, C. A. Goben

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a recombination statistical model for the neutron-induced base current component reported previously. The derivation was based on the following: 1) the current equation for the induced current component developed previously; 2) the Shockley-Read-Hall statistics for holes and electrons; and 3) the recombination statistics derived by Sah, Noyce and Shockley for sites in the bulk space-charge region. The recombination statistics model depends on the diffusion potential, the junction voltage, the activation energy, temperature, and the ratio of capture cross-sections for holes and electrons. The utility of such a recombination statistical model is illustrated by using measured parameters to …

Radiation And Annealing Characteristics Of Neutron Bombarded Silicon Transistors, L. S. Su, G. E. Gassner, C. A. Goben

Electrical and Computer Engineering Faculty Research & Creative Works

Operating a silicon planar epitaxial transistor in the inverse configuration allows one to demonstrate clearly the importance of the neutron-induced base current component and its degradation of the emitter efficiency, and, because of the much larger depletion layer, to compute a volume dependent damage constant applicable to all silicon p-n junctions. The importance of minimizing the absolute change versus relative change in radiation hardening studies is clearly illustrated. Surface effects were found to be significant for transistors mounted in gas-filled cans. The diffusion potential was predicted, on theoretical grounds, to vary with neutron fluence, and the theory was experimentally confirmed. …

Design Of Truncated Sequential Tests For Rapidly Fading Radar Targets, Norval D. Wallace

Electrical and Computer Engineering Faculty Research & Creative Works

Curves and equations are presented from which the exact performance of truncated sequential tests can be determined for one important case: the biased square-law detector for the detection of rapidly fading targets. The method of generating functions is used to derive probability distributions for sample size. It is shown how these probability distributions can be used to determine truncation errors and the effects of multiple-resolution elements. Sample calculations are performed to determine the effects of a particular truncation procedure. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.

Electric Field Investigations And A Model For Electrical Liquid Spraying, Wallace E. Deshon, Ralph S. Carson

Electrical and Computer Engineering Faculty Research & Creative Works

The equation generally used for determining the electric field at the liquid tip in electrical spraying of liquids was originally derived for determining the electric field around a metal tip in the extraction of electrons from metals. In the present paper experimental data were taken at the instant of spraying to determine the validity of using this equation for liquid tips. the results indicate that the value of electric field given by this equation needs to be increased by about 20% in the normal range of operation. A model for the spraying mechanism of the liquid is also presented. © …

Transport Of ⁸⁵Sr And ¹³⁷Cs Under Induced Clay Suspensions, Purush Terkonda

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

“The purpose of this study was to evaluate the effect of induced clay suspensions on the transport of ⁸⁵Sr and ¹³⁷Cs in an aqueous environment.

An instrumented flume was used as a model river to simulate an environment typical of a slow-moving, unpolluted, turbid stream. Modified longitudinal dispersion relationships were used to describe the transport of radionuclides in turbid streams. Data were derived from instantaneous release of ⁸⁵Sr and ¹³⁷Cs with suspended Attapulgite and Kaolinite clays. Continuous release of ¹³⁷Cs with an Attapulgite clay suspension helped to establish uptake and transport characteristics for one environmental …

Australian Tractor Test Report No. 49 : Mccormick International 624, G H. Vasey, W. F. Baillie

Journal of the Department of Agriculture, Western Australia, Series 4

AUSTRALIAN TRACTOR TEST REPORT

No. 49 - McCORMICK INTERNATIONAL 624

A Novel Method For Solving The Uniform Distributed Network Analysis Problem, Robert C. Peirson, Edward C. Bertnolli

Electrical and Computer Engineering Faculty Research & Creative Works

An application of the Laplace transform method of Ogata to the solution of the uniform distributed network analysis problem is described. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.