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General Theory Of Diffusion-Controlled Reactions, Gerald Wilemski, Marshall Fixman

Physics Faculty Research & Creative Works

A formal mathematical description of diffusion-controlled bimolecular reactions is presented. The theory is completely general with respect to the kinds of reaction processes that may be considered. Besides the presentation of the general formalism, the paper also contains several examples illustrating the application of the theory to a simple many-particule system for simple catalytic bimolecular reactions, including fluorescence quenching. The manner in which approximate solutions may be obtained is also outlined.

Performance Degradation Due To Specular Multipath Intersymbol Interference, G. H. Smith, David R. Cunningham, Rodger E. Ziemer

Electrical and Computer Engineering Faculty Research & Creative Works

Plots of performance degradation are used to compare the effects of fading and intersymbol interference in a two-component specular multipath digital communications channel. Similar plots are then used to compare two practical receivers designed to combat the interference. Degradation plots are shown to allow easy identification of each receiver's range of usefulness, as well as identification of variance bounds demanded of channel parameter estimates which the receivers require. Copyright © 1973 by The Institute of Electrical and Electronics Engineers, Inc.

Flowware -- A Flow Charting Method To Describe Digital Systems, Wayne Everett Omohundro

Doctoral Dissertations

"FLOWWARE is an interactive, graphical language to aid in the understanding and design of digital networks. The language is based upon the concept of flow charting. The user specifies the register layout of the system and the sequential operation in the form of a diagram on a graphics terminal. FLOWWARE makes full use of a local minicomputer to perform editing and drawing functions, and a remote large computer to perform translation and simulation. This division of labor allows the user to build his description off-line without having the remote computer program active"--Abstract, page ii.

Considerations In The Design Of A Network Of Minicomputers, Hardy J. Pottinger

Doctoral Dissertations

"The advantages of a network consisting of a number of minicomputers coupled to a large time shared computer are described. This type of network is very useful in the areas of data acquisition, real time control of experiments, and front-end processing for computer graphics.

Problems associated with the development of a network of this type, various possible solutions, and the trade-offs involved are presented. These problems are classified into two categories: the interface between the network and the central computing facility, and the interface between the remote sites and the rest of the network.

The design constraints, rationale, and implementation …

Implementation Of Recursive Algorithms For Delay-Time Estimation Using The Fast Walsh Transform, Donald Robert Nelson

Doctoral Dissertations

"Use of the fast Walsh transform to resolve noisy signals into Walsh function series to digitally implement maximum-likelihood parameter estimators for real-time use is investigated. Realization of estimators which seek a null in the derivative of the log-likelihood function, instead of direct maximization, results in feedback algorithms which yield considerable savings in computation time and storage. Performance of these feedback delay-estimation algorithms is characterized in terms of mean-squared error (MSE) and response to a delay step by Monte Carlo simulation. The effect of changing the number of points in the transform on the MSE is also investigated. Hard limiting of …

Tilt-Table Alignment For Inertial-Platform Maintenance Without A Surveyed Site, Gordon E. Carlson, Max E. Bott

Electrical and Computer Engineering Faculty Research & Creative Works

A method for aligning the rotary tilt table for an inertial-platform maintenance facility without surveying the site is analyzed and evaluated. The method utilizes multiple measurements of the tilt-table azimuth alignment error with different inertial platforms to determine a best estimate of the alignment error. Error analysis indicates that useful facility performance can be obtained with only a small number of measurements. The tilt-table alignment accuracy can be improved as more measurements of the alignment error are made during normal facility operation. © 1973, IEEE. All rights reserved.

Scavenging Of Atmospheric Particles By Water Drops, Ming-Shian Wu

Doctoral Dissertations

"In the first paper, the mechanisms of particle capture and coalescence of aerosols by a moving water drop in the atmosphere are studied using the boundary-layer flow approximation. The particle trajectory is computed by solving the equations of motion of the particle both outside and inside the boundary layer using the Adams-Moulton method. The grazing trajectory is found by a trial-and-error technique. The collision and collection efficiencies of scavenging due to particle inertia and to the velocity gradient of the flow field are then computed for water drops ranging from 0.1 to 1.0 mm in radius and for particle of …

Interior Noise In Military Helicopters, Charles E. Perez Jr.

Masters Theses

"The Temporary Threshold Shift (TTS) or temporary hearing loss caused by excessive interior noise in military helicopters results in a critical degradation of the acoustically unprotected infantryman's ability to detect the existence or the approach of the enemy by hearing under combat conditions. The overall problem of noise reduction in helicopters consists of: (1) identifying the various noise sources, and (2) employing appropriate noise control techniques. Identification of the source is accomplished by the frequency correlation of 1/10-octave band analysis of the interior sound levels measured within the helicopter cabin with near-field sound generated by the sound sources. Reduction of …

A Study Of Rf Induction Heating And Float Zone Refining Of Silicon, John Allen Reynolds

Masters Theses

"Float zone refining using simultaneous RF induction heating and electromagnetic levitation has proven to be the best technique for producing high purity silicon for the semiconductor industry.

A study of the power requirements for floating molten zones, of load to source impedance matching, and of considerations for RF heating coil design was conducted to determine possible methods of improving the technique. It is shown that the power requirements are within reason, that impedance matching can be improved by varying network parameters, and that certain vital items must be assured in the design of different RF heating coils.

It is believed …

Design And Construction Of An Electronic Pressure Altimeter For An Atmospheric Data Acquisition System, Larry Wayne Berkbigler

Masters Theses

"This thesis describes the design, construction, and application of an altimeter which was developed as part of the data acquisition system of a small aircraft used to study atmospheric conditions. The altimeter provides a digital readout and interfaces with analog and digital recorders. It can also provide an audio indication when a predetermined altitude is reached. The altimeter is powered by 12 volts dc, has resolution to 10 feet, and a maximum altitude of 15,000 feet. Its maximum theoretical error is ±78 feet ±0.77% of true altitude, which is an error of ±194 feet at 15,000 feet.

Since the unit …

Numerical Calculation Of The Currents In Bent Wire Antennas, Min Ho Kang

Masters Theses

"The current distribution for bent dipole antennas is numerically calculated by using a digital computer. A delta-gap at the center is assumed for the drive. Several different bend-angles are considered including the cases of the straight wire and the inverted-L. The total length of the wire considered is λ/2 while the ratio of the bent portion over the vertical portion is varied. The method of solution is based on Mei's integral equation and the method of moments. The use of Mei's integral equation eliminates the need for the application of the boundary condition at the point of bending. For …

Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis

Masters Theses

"ESR has been used to study the formation of an amorphous layer in silicon by ion implantation. The room temperature implants were done at 20 keV with low dose rates. The critical dose was determined as a function of ion mass for six different ion species. Our experimental heavy ion results agree with those found by other ESR investigators at higher energy, but are not the same for light ions. However, our light and heavy ion results agree with electron microscope measurements for low energy implants. An energy-independent model for the formation of amorphous silicon by ion implantation has …

Convergence Of Material Balance In Mathematical Simulation Of Petroleum Reservoirs, Abdul Rashid Merchant

Doctoral Dissertations

One criterion for determining the precision of pressures calculated by a simulation model is the accuracy of the material balance. A high degree of precision in the calculated pressures is a necessary condition for elimination of error in prediction of fluid migration in the reservoir. However, this condition is not sufficient to guarantee accuracy of the simulation, since inaccuracies are introduced by truncation errors, machine round-off errors, and by the use of finite difference approximations to represent nonlinear partial differential equations.

A new procedure called Error Matrix Technique has been developed for reduction of material balance errors. This reduction is …

Transient State Analysis Of Separated Flow Around A Sphere, Ching-Liang Lin

Doctoral Dissertations

"Transient state solution of the Navier Stokes equation was obtained for incompressible flow around a sphere accelerating from zero initial velocity to its terminal free falling velocity. By assuming rotational symmetry around the axis in the falling direction, the Navier Stokes equation and the continuity equation were simplified in terms of vorticity and stream function. The instantaneous acceleration of the falling sphere was calculated by considering the difference between the gravitational force and the drag force in a transient state. The governing partial differential equations were non-dimensionalized. A set of implicit finite difference equations was developed. In order to obtain …

Stability Of The Developing Laminar Flow In A Circular Tube, Lung-Mau Huang

Doctoral Dissertations

"An investigation is made of the linear stability of the developing laminar flow of an incompressible fluid in the entrance region of a circular tube. Both axisymmetric and non-axisymmetric small disturbances are considered in the analysis. The stability characteristics of the fully developed flow are also re-examined. The main flow velocity distribution used in the stability analysis is that from the solution of the linearized momentum equation. The governing equations for the disturbances and the boundary conditions constitute an eigenvalue problem which is solved by a direct numerical integration scheme along with an iteration technique. The solution starts with a …

Film Boiling Of Freon 113, Normal Pentane, Cyclopentane, And Benzene From Cylindrical Surfaces At Moderate Pressures, Gary Joseph Capone

Doctoral Dissertations

"An investigation of film boiling heat transfer in saturated pools of liquid Freon 113, Normal Pentane, Cyclopentane, and Benzene was made. The fluids were boiled from copper, cylindrical heat transfer surfaces, 3 inches long, and 0.55, 0.75, and 1.00 inch in diameter. The heat transfer elements were positioned horizontally in an autoclave and tested at moderate pressures of up to a pressure of 242.5 psia for Normal Pentane.

The experimental data are discussed and compared with known film boiling correlations. The known correlations were found to be inadequate in predicting heat transfer coefficients as a function of pressure, temperature difference …

Film Boiling Of Benzene, Freon 113, Freon 11, And Normal Pentane From Horizontal Surfaces At Atmospheric Pressure, Richard Stanley Kistler

Doctoral Dissertations

"A film boiling study was conducted with five different area flat plates at atmospheric pressure for benzene, Freon 113, Freon 11, and n-pentane. The heat transfer surface was horizontal for all tests.

The data were compared to the correlations commonly used for heat transfer. The common correlations were found to be in error for small surface sizes, but adequate for all fluids except benzene for the largest surface, a semi-empirical equation which correlates the available data as a function of surface diameter was derived and discussed"--Abstract, page iii.

Measurement Of Molecular Diffusivities Of Liquid Alkane Systems, James W. Moore

Doctoral Dissertations

"An unsteady-state porous frit method of diffusion coefficient measurement, recently developed in this laboratory, was improved and expanded upon. The experimental technique has been refined and documented. The unsteady-state diffusion of an initially 0.5 N NaCl solution into pure water (effective diffusivity -1.480 x 10^-5 cm²/sec) was employed as the calibration standard. An overall calibration precision of ±4% was obtained. Diffusion times of two hours or less were used for the non-aqueous diffusivity measurements. The validity of this measurement technique was confirmed by the agreement of the measured self-diffusion coefficient of n-heptane (25⁰C) with literature values.

A …

Parameter Identification Applied To Linear Quadratic Differential Games, John D. Corrigan

Doctoral Dissertations

"A two player zero-sum linear quadratic differential game is investigated for the case in which one of the players has incomplete a priori knowledge of the parameters of his opponent's dynamic system. This incomplete system parameter information game is shown to be playable since the ignorant player can make limiting estimates of the unknown parameters from the relative controllability condition for the game. Performance from the ignorant player's point of view is suboptimal.

It is also shown that parameter identification techniques can be applied by the ignorant player in order to directly identify the smart player's closed-loop parameters in the …

The Effects Of High Pressure And Temperature Environments On The Properties Of 6061-T651 Aluminum, Patrick George Davidson

Doctoral Dissertations

"During this experimental testing program the effects of the simultaneous application of high pressure and temperature environments on the mechanical properties of 6061-T651 aluminum were analyzed. From the data obtained at the yield and ultimate points a yield and ultimate model was developed based upon the parameters effective stress, effective strain, and the hydrostatic component of stress. This model was obtained solely from the data acquired from uniaxial tensile specimen tested at various pressures and temperatures. Two other loading paths--biaxial tension and torsion--were then used to verify the accuracy of the model. From the testing program, data were also obtained …

Numerical Simulation Of Heat, Mass, And Momentum Transfer In An Atmospheric Boundary Layer, Darrell W. Pepper

Doctoral Dissertations

"Considerable interest has developed in recent years to understand transport phenomena in thermally stratified boundary layers. More complete knowledge in this field is needed to improve the prediction of the diffusion of air pollutants in the lower atmosphere as well as in forecasting air-water circulation for weather conditions.

The atmospheric boundary layer is modeled using the equations of continuity, momentum, energy, and concentration. Closure of this set of partial differential equations is hindered by the turbulence terms. Using turbulence kinetic energy, the system of equations is closed by internally determining the exchange coefficients of heat, mass, and momentum along with …

Premartensitic Elasticity Of Fe-Ni Invars, Bryce Linn Shriver

Doctoral Dissertations

"The premartensitic temperature dependence of ultrasonic wave propagation in Fe-30 pct Ni polycrystals and Fe-32 pct Ni single crystals was measured by using a continuous wave technique. As the temperature was lowered to within 10°C of the M_s, a nonlinear decrease of the relative shear velocity was observed. This effect is related to dislocation stacking fault instabilities which may trigger the martensitic phase transformation. In addition, the single crystals show a frequency dependence of the shear elastic constant C' well above the M_s. The dispersion is believed to be caused by fluctuations in the anisotropic molecular …

Tchebycheff Approximation On A Discrete Point Set: Algorithms Old And New, William Edward Mcbride

Doctoral Dissertations

"Several linear and nonlinear algorithms for solving the discrete Tchebycheff problem are compared in this study. The Lawson algorithm is compared with two more well-known methods of linear Tchebycheff approximation. A new acceleration scheme for the Lawson algorithm is introduced and its performance is tested with an already existing acceleration technique. The new version is found to be better than the previous one but not as effective as the traditional Exchange method.

A nonlinear version of Lawson's algorithm is proposed for the solution of problems having approximating functions which are varisolvent. Some linear theorems of Lawson are extended to the …

Hall Effect Measurements Of The Net Ionic Mobility In Nacl, Nabr And Nai, Suman Kumar Hukku

Doctoral Dissertations

"Ac Hall effect measurements of the net ionic mobility, µ_H, in "pure" NaCl, NaBr and Nal were made over their intrinsic temperature ranges extending up to about 250⁰ C below the crystal melting point. A well characterized detector system was employed which provided a mobility sensitivity ≥ 2 x 10^-4 cm² · V^-1 · s^-1. Complementary electrical conductivity, σ, data was also collected. The charge transport was assumed to be due to Schottky defects and both cation and anion contributions were considered. The high temperature anion contribution to mobility was clearly demonstrated by …

Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins

Masters Theses

"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …

Nucleate Pool Boiling Of Refrigerant-Oil Mixtures From Tubes, R. L. Dougherty

Masters Theses

"This experimental investigation was conducted to provide design heat transfer data for applications involving the nucleate pool boiling of Refrigerants 11 and 113 from the external surfaces of tubes. Tests were conducted with 0.625-in. o.d. and 1.125-in. o.d. commercial copper tubing; at 1 and 2 atmospheres pressure; and with refrigerant-oil compositions from 0 to 10 percent oil by weight. Results show that each of these parameters can affect the heat transfer coefficient"--Abstract, page ii.

Design Of An Analog-Temperature Control System For An Expansion Cloud Chamber, Andrew C. Tebelak

Masters Theses

"This thesis describes the design, construction, and application of an analog control system for the temperature control of an expansion cloud chamber. During the expansion, the sample gas and the chamber walls are cooled at the same rate so as to maintain adiabaticity. The control system measures the wall temperature with transistor temperature sensors, calculates the gas temperature from the gas pressure using the adiabatic gas law, and generates a control signal proportional to their difference. The control precision is sufficient to allow the chamber to be used in the study of atmospheric phenomena.

The chamber is a ten-sided right …

Design Of A High Pressure Fluid Intensifier, James Andrew Kwiatkowski

Masters Theses

"In this thesis the design of the major components of a high pressure intensifier is presented. The machine is a high pressure fluid intensifier which can develop an intermittent water jet of .01112 inches in diameter at a pressure of 100,000 psi and a flow rate of .9508 gpm. This machine can be used to study the capabilities of high pressure water jets to cut high compressive strength rocks.

The primary machine elements of the intensifier system are the source, charging system, valve system, nozzle, and the intensifier. The source will be a Kobe Triplex Pump having a variable output …

Digital Fault Calculations Of Large Systems Using Matrix Language And Generalized Equations, Saeed Abdel-Halim Khalifa

Masters Theses

"A new short circuit program has been developed for a large system. Several features have been provided to simplify handling of the system data. Various study cases are performed, efficiently, within the available computer memory. A master data bank is established from bus, feeder and transformer data. They can be modified internally to simulate various system configurations. Matrix formation is accomplished using a new sorting method and the IBM/360 Matrix Language MATLAN. A generalized set of ii ·equations have been developed and applied to calculate four types of faults.

The program consists of two phases of operations. In phase-1, input …

Penetration In Granite By Jets From Shaped-Charge Liners Of Six Materials, Ronald R. Rollins, George Bromley Clark, H. N. Kalia

Mining Engineering Faculty Research & Creative Works

A new application of theory for three-dimensional collapse of conical liners shows why the two-dimensional analysis may offer a good approximation. Shaped-charge design parameters and rock target properties were investigated to determine their effects on penetration and breakage. Several metals, liner thicknesses, cone angles and standoff ranges for each were investigated. Effective standoff is greater for aluminum than more dense metals. Jets from the 60° monel, brass and steel liners gave the deepest penetration in granite. Jets from copper and brass liners gave equal penetration for 42° apex angles. Liners containing zinc produced small slugs or none at all. The …