Engineering Commons^™

Dynamic Capacitance Of Metal-Oxide-Semiconductor Field-Effect Transistors, Marion Wendell Tucker

Masters Theses

"A transient peak was observed for MOSFET devices when measuring the dynamic capacitance versus applied gate voltage for various configurations at low frequencies. This peak is absent in conventional steady-state ac measurements. Since the peak is also absent in high grade devices and at high frequencies a possible explanation in terms of surface state traps is discussed for the observed phenomena"--Abstract, page ii.

Chemical Precipitation Of Phosphorous With Sodium Aluminate And Alum In The Activated Sludge Aeration Chamber, Richard Charles Vedder

Masters Theses

"The purpose of this investigation was to study the removal of phosphorus by chemical precipitation with sodium aluminate and alum in the activated sludge aeration chamber, and determine the effect of the aluminum to phosphorus ratio and the mixed liquor suspended solids concentration on the phosphorus removal efficiency and the effect of the precipitants on the removal of organic pollutants in the activated sludge process. The studies were conducted on settled domestic sewage in three bench-scale continuous flow activated sludge units supplemented with jar tests. Major parameters employed included influent and effluent total phosphorus and chemical oxygen demand (COD), mixed …

The N-Wire Exponential Transmission Line, Vernon Ray Stanley

Masters Theses

"This paper deals with the n-wire exponentially tapered transmission line. A characteristic impedance is defined, and the results of terminating in this impedance are investigated. A very long line and the condition of no reflections are considered, and the conclusions are compared. Finally, three specific 3-wire line problems are worked with a characteristic impedance termination and a unit step input"--Abstract, page ii.

Transient Response Of A Class Of Distributed Systems, Jaw-Shyong Tzeng

Masters Theses

"The transient response of uniform distributed systems with any transfer function that is rational in w=e[square root of Ts] can be analyzed with the basic form of the transfer function [1 over (w-a)] after partial fraction expansion, where the pole a can be real or complex in the w plane. with the complex pole within the stable region in the w plane, there are only two possible combinations of the basic transfer function [1 over (w-a)], i.e. [1 over (w-a)] ł [1 over (w-a*)], for physical realizability. The imaginary part of the transient response of the basic transfer function [1 …

A Simulation Of The Transistor By Computer Using The Linvill Diffusion Model, Clifford D. Skouby

Masters Theses

"This investigation involves the construction of an analog computer model of the transistor. The computer model is based upon the Linvill diffusion model. The equations for the Linvill diffusion model were programmed on the computer by making certain approximations. Different models, using different approximations, were used for the different regions of operation of the transistor. A composite analog model was constructed by combining the models for the restricted regions, giving a general model good for all regions of transistor operation. This analog diffusion model was modified to account for the effects of junction capacitance and base resistance. The modified analog …

The Analysis Of A Phase-Locked Loop By The Functional Expansion Method, Hugh Francis Spence

Masters Theses

"The time response of a generalized second order Phase-Locked Loop to step and ramp inputs is described by a functional power, truncated at the third order term. The responses given by the functional power series differs from the analog simulation by less than 6% when the inputs are below 2.0 rad (rad/sec)"--Abstract, page ii.

An Unsteady-State Method For Determining The Thermal Conductivity Of Materials, Richard H. Bulmer

Masters Theses

"Originally this work was initiated to develope [sic] a method for measuring the thermal diffusivity and thermal conductivity of metals. Due to the characteristics of the method and the equipment used, it was concluded that the technique is not suitable for materials of high conductivity. However, results show that the apparatus is valuable for the determination of the thermal diffusivity of relatively poor heat conductors. The favorable characteristics of the method are its rapidity and basic simplicity"--Abstract, page ii.

A Formal Description Of The Scc 650 Digital Computer, Hardy J. Pottinger

Masters Theses

"The requirements of a descriptive language for automated digital computer design are presented. Y. Chu's Computer Design Language is then used to describe the logic of the SCC 650, a small general-purpose digital computer at UMR. Chu's language is found to be the best language available to the designer for both documentation and automatic translation into Boolean Equations"--Abstract, page ii.

An Ultrasonic Pulse Generator Using The Transducer As A Frequency Determining Element, Donald E. Watke

Masters Theses

"This paper describes the development of a method of ultrasonic pulse generation in which the transducer determines the frequency of oscillation. A definite advantage of this method is the ability of the frequency of oscillation to change with changes in the transducer mechanical resonant frequency. This maintains peak efficiency at all times. The method is demonstrated in a small sonar transmitter but could be applied to any area involving driven ultrasonic transducers"--Abstract, page ii.

Kinetics Of The Formation Of Strontium Zirconate, W. H. Parker

Masters Theses

"The decomposition rate of strontium carbonate (SrC0₃) was measured using a TGA apparatus. It was found to deviate slightly from zero order classical reaction. The rate of formation of strontium zirconate (SrZr0₃) from zirconium oxide (ZrO₂) and strontium oxide (SrO) in the form of the decomposition product of SrCO₃ was measured using quantitative x-ray diffraction for mineralogical analysis. It was found to most nearly follow the Zhuravlev-Lesokhin-Tempel' man rate equation. The rate of decomposition of strontium carbonate was found to be more rapid than the rate of formation of strontium zirconate such that for the most part strontium oxide is …

A Study Of Porous Membrane Evaporation For Desalination In A Flow System, Jing Ming Lee

Masters Theses

"The purpose of this investigation was to study the simultaneous mass and heat transfer mechanism in evaporation through a porous membrane with a non-wettable surface. Such water repellent membranes permit the passage of water vapor, but not liquid water. The investigation concerned the mass transfer rate through the membrane pores with flow on one or both sides of the membrane. The water-repellent membrane separated a hot salt solution from the fresh water, and a copper sheet separated the fresh water from a cold salt solution. A three-channel evaporator-condenser was used, and the membrane consisted of glass fiber paper treated with …

Investigation Of Thermal Resistance At The Interface Of Dissimilar And Similar Metals, Ching-Liang Lin

Masters Theses

"Experiments have been conducted to investigate the resistance and the effect of the directional heat flow at the interface of metals in contact. The test specimens were cylinders, axially aligned and dead weight loaded. Specimen materials were aluminum, bronze, and steel. The tests were conducted at environment pressures of 5x10⁻⁵ Torr. or less. The dead weight load was kept at 10 lbs. for all tests and the surface roughness for all specimens was from 6 to 8x10⁻⁶ inch. The results of the investigation reveal that the resistance to heat flow at the interface of metals decreases as the interface temperature …

Constant Horizontal Force Machining Through Flash Welded Steel Bars Of Varying Hardness, Donald Naeger

Masters Theses

"The purpose of this experiment was to determine the effect of a constant horizontal force applied to the carriage of a lathe as it turned a piece of stock which consisted of two steel bars, of different hardness, flash welded together. This experiment was performed on a lathe to which a pulley system with a mechanical advantage of six was attached to the carriage. The strain on the tool was measured both in the horizontal and vertical directions by a tool dynamometer on which eight strain gages were mounted. The strain gages were calibrated on a Tinius-Olsen testing machine. The …

An Intensity Regulation System For A Monochromator, David A. Wayne

Masters Theses

"In the investigation of phenomena involving both optical intensity and wavelength, an instrument is often desired which allows one of the quantities to be held constant while the other is varied. A relatively inexpensive system is described which utilizes a commercial grating monochromator and external feedback electronics to regulate the output intensity as the wavelength is varied. In this system, a sample of the output intensity is taken by a photosensor with known spectral response. The output of the photosensor is then compared electronically with that of a pre-programmed function generator which cancels nonlinearities in the photo-sensor. The resulting signal …

The Modeling, Fabrication, And Testing Of An Instantaneous Torque Measuring System, Thomas Phillip Hertel

Masters Theses

"The purpose of this work was to obtain a measuring system to experimentally determine the instantaneous magnitude and frequency of the torques from zero to 2400 Hertz produced by a single phase motor. This paper explains the methods employed in designing and fabricating a measuring system and shows the results from tests using this equipment. It was found that a measuring system based on the determination of the instantaneous value of the stator's reaction torques could be realized. Also, it was found that some simple methods of computation could be used to find the magnitudes of the frequency components comprising …

Determination Of Molecular Diffusivities In Liquids, Pai-Chuan Wu

Masters Theses

"A porous plate, initially at a uniform solute concentration is immersed in a well-stirred pure solvent bath of known volume. It is desired to find the molecular diffusivity of the solute-solvent system by observing the change of the solute concentration in the solvent bath with time. In this study, concentration-time data were curve-fitted by non-linear, least squares techniques to the various mathematical solutions describing molecular diffusion in the porous frit. This technique is used to determine the diffusion coefficient and predict the value of other parameters existing in the different mathematical diffusion models. The results from the different models are …

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 …

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 …