Engineering Commons^™

Simulation Of Digital Computer Simcom, Ming-Te Hsieh

Masters Theses

"SIMCOM(SIMulated COMputer) is a hypothetical small general-purpose digital computer. It has a core memory of 4096 12-bit words and has been modeled after the Scientific Control Corporation SCC 650. The instructions of SIMCOM are completely compatible with the SCC 650, any SIMCOM program can be run on the SCC 650. The logical organization is similar but not identical to the SCC 650, the mnemonics that are used to represent all instructions are identical to those used on the SCC 650 except the Input/Output instructions. This computer can be simulated on any available commercial computer. If such a simulation is available, …

Low Frequency Lumped Element Directional Couplers, Constantine Rodolph Jenkins

Masters Theses

"Lumped element directional couplers are desirable at frequencies below the VHF range because they eliminate the large physical size necessary for the distributed element directional couplers. The purpose of this work is to describe the theory and design of such low frequency lumped element directional couplers. A model for the coupler is developed and the equations which describe it are derived. Scattering matrices for one and two section couplers are obtained. Computer solutions for three section couplers are presented. Experimental results for one, two, and three section couplers are presented and comparison with theory are made. Comparisons of theoretical and …

Frequency Division Using Cascaded Phase-Locked Loops, Curtis B. Abshier

Masters Theses

"In many practical communication systems it is necessary to generate phase coherent subharmonics of an input tone. A useful system for accomplishing this task is a system of phase-locked loops in cascade. It is shown that when the feed-forward function is matched, the phase error of the second loop is zero. Analytical analysis and computer simulation prove that the minimum time to achieve phase-lock is obtained when the feed-forward function is matched. Under this condition, necessary design parameters are determined with ease"--Abstract, page i.

Design Of A Quadrature Envelope And Correlating Receiver, Clinton Harold Moor

Masters Theses

"A receiver design analysis and rationale is presented. The receiver is capable of performing in an instrumentation role for propagation experiments conducted in the field. The data gathered during the field tests will be used to determine the complex impulse response of the ground-to-ground communications channel and to evaluate the performance of a candidate ranging waveform in this channel. The receiver is capable of operation in either the propagation mode or the ranging mode and each mode of operation can be performed on either a UHF band frequency or an L-Band frequency. During the propagation mode the receiver serves as …

An Analysis Of Solar Noise Outbursts And Their Application To Space Communication, Marion Francis Moen

Masters Theses

"A relationship between sunspot activity, solar flare activity and noise outbursts is presented. Five different types of interference radiation in the 10MH_z to 30,000 MH_z frequency band are discussed. Data obtained by solar radio astronomy are analyzed to determine the extent of solar noise outbursts as a function of sunspot activity. An application of the burst data to future space communication is given"--Abstract, page ii.

Variable-Threshold-Mixed-Weight Threshold Element, Cheng-Chung Liu

Masters Theses

"A threshold element (TE) is a mathematical model of a class of logic gates. The desirability of a threshold element in the application of digital systems stems from its richness of logic power and its relative economy. On the other hand, the tighter tolerences required by the threshold logic element as compared to conventional logic gates have prevented them from being utilized extensively. The purpose of this thesis is to propose a versatile threshold element having high noise immunity and loose tolerance requirement. The proposed TE which has variable threshold and mixed weight capability uses current switching to enhance noise …

A Time And Frequency Domain Approach To The Optimization Of Linear Multivariable Regulators, Eugene Charles Machacek

Masters Theses

"Optimal design and analysis of a multivariable regulator may be achieved in either the frequency or time domain. This paper describes the formulation of the matrix Riccati equation in the time domain and the Wiener-Hopf equation and the root-square-locus in the frequency domain. The necessary requirements which must be satisfied in order to achieve an optimal control vector when using a quadratic performance index are presented for both domains. The resultant optimal control vector is shown to be a linear function of the system state vector. The effect of the quadratic performance index weighting matrices on the optimal system closed-loop …

Density Distribution Measurements In Rarefied Gases Contained Between Parallel Plates At High Temperature Differences, Darryl J. Alofs, Richard C. Flagan, George S. Springer

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Density Distributions Were Experimentally Determined in Rarefied Gases at Rest Contained between Two Parallel Plates Maintained at Widely Different Temperatures. the Temperatures of the Hot and Cold Plates Were ∼79°K and ∼294°K, Respectively, Resulting in a Temperature Ratio of About 4:1. Both Helium and Nitrogen Were Used as Test Gases. Particular Attention Was Focused on Obtaining Data in the Temperature Jump and Transition Regimes. the Gas Densities Were Measured by Observing the Luminescence Produced by a High-Energy Electron Beam Traversed between the Plates. in Addition to the Density Measurements, Heat Transfer Measurements Were Also Made in Order to Estimate the …

Charges On Jet Drops Produced By Bursting Bubbles, Robert A. Medrow, B. T. Chao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The sizes and charges of jet drops produced by bursting air bubbles are examined experimentally. The variation in charge for bubble lifetimes of up to 200 sec in NaCl and KCl solutions is reported. Jet drops refer to drops produced by a jet rising from a cavity left in a liquid surface by a bursting bubble; bubble lifetime is the interval during which a bubble is in motion between generation and rupture. With other variables held constant, drop charge shows a characteristic variation of a rise to a maximum followed by a decrease to an asymptotic value, as bubble lifetime …

Floating Bubble Configurations, Robert A. Medrow, B. T. Chao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The configurations of bubbles floating at a vapor-liquid interface are investigated both analytically and experimentally. The differential equations governing the shape of a single bubble at rest in a liquid of infinite extent are deduced under the assumption of zero dome thickness, uniform surface tension, and equal gas densities within the bubble and above the interface. These equations show that nondimensional bubble shapes depend upon the value of a single parameter. An analytical solution, valid for small bubbles, is developed and shown to be in good agreement with the general numerical solution. Good agreement with theory is demonstrated for floating …

Heat Transfer From An Oscillating Horizontal Wire, Bassem F. Armaly, D. H. Madsen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The effect of vibration on heat transfer by natural convection has been investigated experimentally using a thin wire, 0.010 in. in diameter, and air as a convection medium. Horizontal reciprocating motion of varying amplitudes, peak-to-peak values of 0-2.655 in., and frequencies, 0-20 cps, was applied to an electrically heated horizontal wire. The average wire velocity (frequency times total path length traveled per cycle by the wire) was used to correlate and predict the experimental results. © 1971 by ASME.

Maximum-Distance Linear Codes, Gary K. Maki, James H. Tracey

Electrical and Computer Engineering Faculty Research & Creative Works

Described here is a linear code that has a maximum distance between codewords of k for a code of order 2k. Since the minimum-maximum distance is k for a code of order 2k, a class of minimum-maximum distance codes results. For an (n,k) linear code, k ≤ n ≤ k + k∣2 for k even and k ≤ n ≤ k + (k - 1)/2 for k odd. Maximum-distance codes are found useful in encoding the states of sequential circuits. © 1971, IEEE. All rights reserved.

Deriving Dc Machine Torque By The Principle Of Virtual Work, George Mcpherson

Electrical and Computer Engineering Faculty Research & Creative Works

The purpose of this paper is to fill a gap which exists in the "textbook" theory of dc machines. The paper shows that the usual expression for dc machine torque can be obtained from the direct application of the principle of virtual work to the machine, making the traditional assumptions. The method provides additional benefits in that it demonstrates the reluctance torque which results from the saliency of the field structure and shows that compensating windings have no effect on the torque under the assumed linear conditions. Copyright © 1971 by The Institute of Electrical and Electronics Engineers, Inc.

Electrical Engineering Education In An Industrial Laboratory, J. Derald Morgan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a unique electrical engineering laboratory course. This laboratory is an example of industry-uni-versity cooperation in engineering education. The organization and operation of the course is outlined and explained. The educational benefits derived from such cooperation between industry and the university are briefly detailed. These benefits are extended to the students, the university, the faculty, and the participating industry. This paper provides the framework and challenge to industry from which other laboratory experiences can be conceived and developed. Copyright © 1971 by The Institute of Electrical and Electronics Engineers, Inc.

A State Assignment Procedure For Asynchronous Sequential Circuits, Gary K. Maki, James H. Tracey

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new procedure for constructing nonuniversal shared-row internal state assignments for asynchronous sequential circuits. The method consists basically of establishing an initial code with the minimum number of variables required to dis. © 1971, IEEE. All rights reserved.

A Stable Explicit Method For Simultaneous Quasi‐Linear Differential Equations, Roy J. Brunson, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

The Anodic Dissolution Of Tungsten, James W. Johnson, Cheng-Hsiao Wu

Chemical and Biochemical Engineering Faculty Research & Creative Works

The anodic dissolution of tungsten was studied in H₂SO₄-K₂SO₄ solutions (pH = -2 to 2.5) and K₂SO₄-K₂CO₃-KOH solutions (pH = 11.5 to 14.5) at 25 C. Faradaic efficiency studies in basic solutions showed the metal to be oxidized to the +6 state. In acid solutions, a thick protective film of yellow WO₃ was formed. Polarization curves possessed linear Tafel regions (slope ~ 2.3 RT/F) at potentials slightly more positive than the rest potentials. An anodic dissolution mechanism is proposed which involves a surface film …

Mass Transfer Inside Liquid Droplets And Gas Bubbles Accompanied By A Second‐Order Chemical Reaction, R. J. Brunson, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Diffusion Coefficients Of Ethylene Glycol And Cyclohexanol In The Solvents Ethylene Glycol, Diethylene Glycol, And Propylene Glycol As A Function Of Temperature, Ronald D. Mitchell, James W. Moore, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Organic Desorption From Carbon-I. A Critical Look At Desorption Of Unknown Organic Materials From Carbon, S. C. Allen, R. H. Pahl, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Anodic Dissolution Of Beryllium In Anhydrous Media, William Joseph James, Martin E. Straumanis

Chemistry Faculty Research & Creative Works

No abstract provided.

Open-Channel Profiles By Newton's Iteration Technique, D. L. Fread, Terence E. Harbaugh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Computation of surface profiles for steady gradually varied flow can be accomplished by use of Newton's Iteration Technique. The magnitude of error is controlled and the profile depth can be conveniently calculated at selected distances upstream or downstream from a control point. A Fortran IV program is provided for utilizing the technique in a trapezoidal channel. © 1971.

Sufficiency Conditions For Constrained Optima, Ju-Chang Huang, Robert M. Wellek

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Sufficiency conditions for constrained optimization problems were derived by the use of constrained second total derivatives. The results are in a simpler form than the Schechter and Beveridge relation. The sufficiency conditions of Phipps were corrected. © 1971, American Chemical Society. All rights reserved.

Permeability Scaling In A Numerical Coning Model, V. K. Dutta, Marion D. Arnold

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A method is described for simulating coning into a wellbore using a numerical simulation model. The method allows the wellbore cells to be considerably larger than the actual wellbore. This makes coning studies feasible using an implicit pressure-explicit saturation type model with a reasonable time step. This capability is achieved by scaling the horizontal-vertical permeability ratios to give the proper vertical potential drop.

The Anodic Dissolution Reaction Of Insb: Etch Patterns, Electron Number, Anodic Disintegration, And Film Formation, Martin E. Straumanis, Lih Da Hu

Materials Science and Engineering Faculty Research & Creative Works

The etching behavior of the inverse {111} planes of undoped, semiconducting, n-type, InSb single crystals was explored. Depending upon the etchant, including anodic dissolution, various etch patterns were obtained on the inverse planes. In general, the etch pits on the In{111} plane were round, and the face was shiny, whereas the face of the inverse plane was dark and rough. The rates of dissolution in the electrolytes used were very low, especially in absence of oxidizers. The components dissolve as In3+ and Sb3 +. At current densities above 40 or 60 mA cm-2 (on Sb{111} or In{111}), growth of a …

A Magnetic Aftereffect In Dilute H.C.P. Co-C Alloys, J. R. Keiser, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

A magnetic Dis accommodation in dilute h.c.p. Co-C alloys has been observed around 90°C. The thermally activated process giving rise to the Dis accommodation is characterized by an activation energy of 26 kcal mole-1 and an attack frequency on the order of 10+13 sec-1. An application of the selection rules shows that the Dis accommodation cannot be caused by the redistribution of tetrahedral or octahedral interstitials or any nearest neighbor interstitial pairs as long as the defects interact linearly with the internal magnetic field. © 1971.

On The Activation Entropy Of Interstitial Diffusion In B.C.C. Iron, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

The Effect Of A Knurled Heat Transfer Surface Upon Pool Nucleate Boiling Of Normal Pentane, Jerry James Carr

Doctoral Dissertations

"The effect of knurling a nucleate boiling heat transfer surface was studied. The knurling utilized produced regular, four-sided, adjacent pyramids with an apex angle of 90 degrees. Four knurling densities were used ranging from 416 to 2591 pyramids per square inch. The transfer surface was gold-plated copper and the heaters used were electrically heated, ten-inch long, horizontal cylinders of one-inch diameter. The liquid boiled was normal pentane at its saturation temperature and a pressure of 760 millimeters mercury.

For some of the knurled surfaces the temperature difference required to produce a given heat flux was found to be less than …

Low-Energy Electron Transport By The Method Of Discrete Ordinates, David E. Bartine

Doctoral Dissertations

"The one-dimensional discrete ordinates code ANISN has been adapted to simulate the transport of low-energy (on the order of a few MeV) electrons. Two different calculational techniques have been utilized for the treatment of electron-electron collisions that result in a small energy transfer. One method treats such collisions by a continuous slowing-down approximation, while the other method treats these collisions by the use of a very approximate cross section. Calculated results obtained with ANISN are compared with experimental data for the transmitted energy and angular distributions for 1-, 2.5-, 4-, and 8- MeV electrons normally incident on aluminum slabs of …

Use Of The Turbulence Kinetic Energy Equation In Analyzing Turbulent Near Wakes, James Edward Auiler

Doctoral Dissertations

"A general method is presented for analyzing turbulent flow fields in the near wake regions of two-dimensional and axisymmetric bodies. The governing partial differential equations of continuity, momentum and turbulence kinetic energy are expressed in elliptic form in terms of the dependent variables stream function, vorticity and turbulence kinetic energy. An iterative finite-difference technique is used to solve the governing equations simultaneously. Numerical solutions are obtained for the following physical problems: 1. Laminar near wake: Only stream function and vorticity are considered for laminar flow. Solutions are compared with available analytical results for uniform flow over a sphere. 2. Turbulent …