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A Driver-Assisting Control System, Roger Allen Hayes Jan 1971

A Driver-Assisting Control System, Roger Allen Hayes

Masters Theses

"The material presented here explains the electronics of a magnetic guidance control system. The system is based on magnets embedded in the center of the roadway. If a vehicle passes near a magnet, fluxgate magnetometers sense the presence of the magnets and guidance pulses are developed and processed. The end result is a visual output which indicates the direction the driver must steer the vehicle for proper positioning on the roadway. The paper presents a solution to the detection problem caused by the sensor output being a function of the earth's field as well as the field of the guidance …

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Stability And Synthesis Of Transfer Functions Rational In W = E To The Power Of The Square Root Of T (S² + Bs + C) And Omega = The Square Root Of T (S² + Bs + C), James Fred Archer Jan 1971

Stability And Synthesis Of Transfer Functions Rational In W = E To The Power Of The Square Root Of T (S² + Bs + C) And Omega = The Square Root Of T (S² + Bs + C), James Fred Archer

Masters Theses

"The bounded input-bounded output stability is investigated for networks containing uniformly distributed LRGC, LRC, GRC and G(ω)RC elements. The region of stability in the W plane (W = e to the power of the square root of (s² + bs + c), Θ plane (Θ = the square root of (s² + bs + c), and S plane (S = s²+bs+c) is found in each case so that if the poles of a transfer function rational in W, Θ or S lie within this region the system is stable. After obtaining a desired transfer function rational in W = e …

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Synthesis Of Active Distributed Rc Networks Via The W=E[Superscript Square Root Of S] Transmission, Roy Dale Hensley Jan 1971

Synthesis Of Active Distributed Rc Networks Via The W=E[Superscript Square Root Of S] Transmission, Roy Dale Hensley

Masters Theses

"The material presented here provides a means for synthesis of networks containing uniformly distributed RC elements. After transforming the desired transfer function into a function rational in W = e[superscript square root of sRC] , state-variable synthesis methods are applied to obtain a model containing elements with transfer functions of the form 1/W. A circuit is then presented for the 1/W block along with error analysis and design procedures for use in construction of the model. The elements of the synthesis procedures of Wyndrum and O'Shea are presented for comparison. Furthermore, synthesis of functions rational in W and Θ = …

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A Study Of A Nitrogen Heat Pipe, Jay Dudheker Jan 1971

A Study Of A Nitrogen Heat Pipe, Jay Dudheker

Masters Theses

"An experimental heat pipe, 33.25 inches long and 0.75 inches in diameter, with modacrylic fiber wick and liquid nitrogen as its working fluid was constructed to study the operating characteristics of a cryogenic heat pipe. The effective thermal conductivity and the axial temperature distribution were determined for various levels of power input. The effect of inclination angle on the above parameters was also measured"--Abstract, page ii.

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Free Vibrations Of Circular Cylindrical Shells, Sushil Kumar Sharma Jan 1971

Free Vibrations Of Circular Cylindrical Shells, Sushil Kumar Sharma

Masters Theses

"In this report bending theory of shells is used to determine the natural frequencies and mode shapes of circular cylindrical shells. The governing eighth-order system of differential equations has been put in a form which is especially suitable for numerical integration and application of different sets of homogeneous boundary conditions. The Holzer method is used to solve the eigenvalue problem. During numerical integration of the differential equations, the exponentially growing solutions are suppressed whenever they become larger than previously selected values. Numerical results are obtained for various shell geometry parameters and for three different sets of homogeneous boundary conditions. These …

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Evaluation Of A Cation Isotopic Substitution Technique In Conjunction With A High Temperature Gas Pycnometer For Determining The Stoichiometry Of Materials, Michael Clair Graves Jan 1971

Evaluation Of A Cation Isotopic Substitution Technique In Conjunction With A High Temperature Gas Pycnometer For Determining The Stoichiometry Of Materials, Michael Clair Graves

Masters Theses

"This study was concerned with the evaluation of a high temperature gas pycnometer, used in conjunction with a cation isotopic substitution technique, for determining the stoichiometry of materials. Three methods were investigated for determining the correction factors for the thermal gradient effects in the gas pycnometer. The correction factors were shown to be dependent on the temperature, the sample volume, and the height of the sample in the sample chamber. Under the conditions of these experiments, the correction factors were shown to be essentially independent of sample grain size and pycnometer atmosphere. The determination of the stoichiometry of cadmium oxide …

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The Influence Of Temperature, Carbon Content, And Preloading On Secondary Consolidation Of A Clay, Richard Kai-Ming So Jan 1971

The Influence Of Temperature, Carbon Content, And Preloading On Secondary Consolidation Of A Clay, Richard Kai-Ming So

Masters Theses

"The effect of temperature, organic carbon content, and preloading on secondary consolidation of Bryce clay has been studied. A straight line plot of void ratio versus logarithm of time was established in secondary consolidation for long term loading periods up to one month. Temperature changes within the range of 5ºC. to 45ºC. were studied in the secondary consolidation phase at different stress levels and different carbon contents of the soil. Secondary consolidation in a preloading cycle at a stress level of 2 tsf unloaded to 1 tsf and reloaded to 2 tsf was studied. The preloading tests were at temperatures …

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Irradiation Enhanced Decomposition Of A Nickel-Carbon Solid Solution, Bryce Linn Shriver Jan 1971

Irradiation Enhanced Decomposition Of A Nickel-Carbon Solid Solution, Bryce Linn Shriver

Masters Theses

"This investigation was performed to determine the effects of room temperature neutron irradiation on the distribution of carbon in a nickel--0.3 wt. % carbon alloy. The experiment consisted of comparing the amount of carbon in solid solution and the internal stresses of both unirradiated and irradiated (10¹³ fn-cm⁻² < ΦF < 10¹⁸ fn-cm⁻²) samples following isochronal anneals between 100ºC and 1200ºC by using the magnetic disaccommodation technique. The results indicate that the amount of carbon remaining in solid solution decreases with increasing neutron dose. At temperatures below 200ºC this is due to the trapping of carbon by mobile irradiation-produced defects. Between 200ºC and 600ºC the formation of metastable carbides is enhanced by the presence of irradiation-produced defects. No differences are observed in irradiated and unirradiated samples above 600ºC"--Abstract, page iii.

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The Effect Of Cathodic Protection On The Stress Corrosion Characteristics Of 300m Low Alloy Steel, John Pechonick Jan 1971

The Effect Of Cathodic Protection On The Stress Corrosion Characteristics Of 300m Low Alloy Steel, John Pechonick

Masters Theses

"The objective of this investigation was to determine if stress corrosion failure of 300M steel is accelerated by the application of cathodic protection. Testing was conducted on notch tensile specimens that were coated with vacuum cadmium, electroplated cadmium, and vacuum aluminum. All specimens were stressed and placed in an aqueous sodium chloride environment. The failure times for the specimens were monitored and graphs were drawn which characterized the stress corrosion resistance of 300M steel and the cathodic protection systems. Fractography techniques were used to study the failure surfaces to determine the type of failure mechanism. The results of this thesis …

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A Study Of The Effects Of Mixing On The Accelerated Anaerobic Digestion Of Concentrated Municipal Sludges, Victor Darryl Orr Jan 1971

A Study Of The Effects Of Mixing On The Accelerated Anaerobic Digestion Of Concentrated Municipal Sludges, Victor Darryl Orr

Masters Theses

"Most domestic sewage treatment plants today practice anaerobic digestion of sludge. The purpose of this investigation was to determine if thorough mechanical mixing of concentrated sludge would improve its digestion. The simulated digesters consisted of six 1 gallon anaerobic reactors which were operated in the laboratory for 78 days. The contents of three digesters were continually mixed and their responses were compared with those of the similarly loaded remaining three unmixed units. Raw sludge with solids concentrations of 7.5, 15 and 30 per cent was digested for detention periods of 30, 15 and 7.5 days at 33º C. Various analyses …

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The Effect Of Solvents On The Desorption Of Phenol From Carbon In A Water Free System, William W. Knickmeyer Jan 1971

The Effect Of Solvents On The Desorption Of Phenol From Carbon In A Water Free System, William W. Knickmeyer

Masters Theses

"The desorption of phenol from active carbon was studied using a continuous flow desorber. The system used was nearly water free to reduce water-phenol interactions. The ten solvents used in this study exhibited a wide difference in their desorption capabilities. An attempt to correlate the desorption data with the physical properties of phenol and solvents, in addition to regular solution theory, proved unsuccessful. A thermodynamic approach using the linear free energy-enthalpy relationship produced a general trend by using the heat of solution for phenol in solution and a reasonable correlation using the heat of formation of the phenol-solvent hydrogen bond …

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Evaporation And Condensation Of Zinc, Shailesh Bhanuprasad Vora Jan 1971

Evaporation And Condensation Of Zinc, Shailesh Bhanuprasad Vora

Masters Theses

"Evaporation rates of liquid zinc were determined experimentally within the temperature range of 450º C to 575º C and at argon pressures ranging from 730mm Hg to 130mm Hg. Extrapolated values of these rates are found to be consistent with the previously reported rates obtained by St. Clair and Spendlove at lower pressures. Between 100 microns and one atmosphere pressure rates of evaporation seem to vary according to an equation of the form W = APᴮ, where Pis pressure and, A and B are constants. Similar experiments were performed with brass powders in atmospheres of argon and helium at temperatures …

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An Analog Computer Simulation Of The Flapping Of A Helicopter Hinged Main Rotor Blade, Edward Charles Robinson Jan 1971

An Analog Computer Simulation Of The Flapping Of A Helicopter Hinged Main Rotor Blade, Edward Charles Robinson

Masters Theses

"An analog computer simulation was performed on the Systron Donner SD 40/80 electronic differential analyzer consisting of one panel (SD 40) less three modules augmented by three digital logic modules for iterative operation. The flapping equation was solved in continuous iteration for various values of blade mass and the resultant blade flapping magnitudes and harmonic coefficients were compared in computer plots of the blade tip path plane. A flap compensator was added and the result plotted. Various aerodynamic parameters of the flapping equation solution were plotted"--Abstract, page ii.

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Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr. Jan 1971

Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr.

Masters Theses

"Internal friction and sodium and potassium self-diffusion coefficients for (1-X)Na₂O · XK₂O· 3SiO₂ glasses were measured. Alkali diffusion was measured between 300 and 500ºC using radioactive isotopes and a thin-sectioning technique. Internal friction was measured from room temperature to 500ºC, 0.1 to 2000 Hz. Comparison between alkali diffusion and internal friction data for Na-K glasses with those for other mixed-alkali glasses shows that the mixed-alkali peak is related to alkali mobility. It is concluded that the mechanism for mixed-alkali internal friction is a cooperative rearrangement of dissimilar alkali ions, with the slower moving ion controlling the rate of reorientation"--Abstract, page …

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Electrolytic Reduction Of Zinc From Acidic Sulfate Solutions, Kenneth Dale Gielow Jan 1971

Electrolytic Reduction Of Zinc From Acidic Sulfate Solutions, Kenneth Dale Gielow

Masters Theses

"Cathode polarization curves were obtained for the electrodeposition of zinc from sulfate solutions with pH 2 and zinc concentrations of 10.0, 40.0, 80.0, and 100.0 gpl zinc. Both pure zinc and pure aluminum were used as cathodes with some difference in results noted. The effect of animal glue additions of 0.01, 0.10, and 0.50 gpl of solution on the cathodic polarization curves and the resulting deposit morphologies were determined. These glue additions correspond to 0.20, 2.0, and 10.0 pounds of glue per ton of zinc deposited, respectively. The slope of the Tafel region of the polarization curves was found to …

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Reservoir Design: Simulation Techniques, Larry W. Mays Jan 1971

Reservoir Design: Simulation Techniques, Larry W. Mays

Masters Theses

"A simulation model is developed to aid in the analysis of small dams to reduce the possibility of inadequate spillway designs. Basic assumptions concerning the geometric aspects of the natural reservoir are made to develop the model which is based upon describing the timing and magnitude of a design flood passing through a reservoir. Simulation equations are derived from the basic continuity equation and describe reservoir outflow and storage as functions of reservoir depth. Newton's Iteration Technique is utilized to solve the simulation equations for the reservoir depth. The resulting simulation model determines an optimum size auxiliary spillway having a …

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An Energy Solution For Vibration Characteristics Of Free Thin Cylinders, Dale Elmer Leanhardt Jan 1971

An Energy Solution For Vibration Characteristics Of Free Thin Cylinders, Dale Elmer Leanhardt

Masters Theses

"In this report the flexural vibrations of the walls of free, thin, circular cylinders are considered. Theoretical expressions are developed for the natural frequencies by extending the approximate energy method of Arnold and Warburton to the free-free case. Furthermore, the developed expressions are shown to apply, as special cases, to the fixed-fixed and simply-supported cylinders analyzed by Arnold and Warburton. The energy solution for free-free cylinders is checked both experimentally using a 3500 pound-force, 5 to 2000 hertz, vibration exciter and numerically using the well documented SABOR IV-DYNAL finite element program. While the derived energy method accounts for any prescribed …

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Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang Jan 1971

Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang

Masters Theses

"The anodic oxidation of EDTA was studied in acid sulfate solutions on platinized-Pt at 25ºC. Polarization relationships were obtained for the EDTA concentration range 3. 42 x 10⁻⁵ to 3. 42 x 10⁻³ M and pH range 0. 35 to 3. 80. Numerous reaction products were identified that indicated a sequential removal of acetate groups from the EDTA, each by an initial decarboxylation followed by a reverse Schiff-type reaction, that produced formaldehyde and the corresponding amine. A reaction sequence which correlated the experimental data involved Frumkin-type adsorption of the EDTA species through an unionized acetate group followed by a rate-determining …

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A Closed Form Method For Predicting The History Of Circular Orbit Altitude Decay Of A Near-Earth Satellite Including The Effect Of A Dynamic Atmosphere, John Copley Buchholtz Jan 1971

A Closed Form Method For Predicting The History Of Circular Orbit Altitude Decay Of A Near-Earth Satellite Including The Effect Of A Dynamic Atmosphere, John Copley Buchholtz

Masters Theses

"A closed form expression for the time to decay between two circular orbit altitudes is developed. The long-term dynamic variation of high altitude atmospheric density is included. The density is approximated as a ratio of two quadratics with the numerator being a function of the time-related exospheric temperature and the denominator being a function of altitude. The 11-year cyclic variation of exospheric temperature is then represented as a piecewise linear function of time. The analytic expression for circular orbit altitude decay rate is developed by describing the energy loss due to atmospheric drag. A point mass representation of the Earth's …

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The Influence Of Member Length On Thermal Contact Resistance In A Vacuum Environment, Larry Martin Cooper Jan 1971

The Influence Of Member Length On Thermal Contact Resistance In A Vacuum Environment, Larry Martin Cooper

Masters Theses

"An investigation was conducted to determine the influence of member length on thermal contact resistance in a vacuum environment. A model was created which consisted of a center rod axially loaded between two other members. It was assumed that circular macroscopic constriction areas were formed at the contact interface when the rods were loaded. Macroscopic modeling of the contact surfaces makes the thermal contact analysis a function of the mechanical and thermal boundary conditions of the total body. The method of finite differences was employed to calculate the temperature distribution, heat flows, and thermal contact resistance of each member. Data …

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Laminar Heat Transfer For Small Prandtl Number Fluids Including Step Change In Wall Temperature, Shiny Ting Jan 1971

Laminar Heat Transfer For Small Prandtl Number Fluids Including Step Change In Wall Temperature, Shiny Ting

Masters Theses

"The object of this investigation is to provide a simple means of determining the heat transfer from a flat plate which has an unheated leading length x₀. The case of steady, two-dimensional, laminar flow of an incompressible fluid with a Prandtl number of less than one is considered. Since there exists an unheated length and the Prandtl number of the fluid is less than one, the thermal boundary layer intersects the flow boundary layer. Thus, the solution of the problem divides into two regions. In this study, the problem is solved analytically by employing the energy integral equation. The temperature …

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Compressibility Effects On Transient Gas Pipe Flow, Gerald Francis Mouser Jan 1971

Compressibility Effects On Transient Gas Pipe Flow, Gerald Francis Mouser

Masters Theses

"Abstract (1) Methods of iterative solution for the partial-differential equations that govern the transient flow of gases in pipelines are obtained by using the method of characteristics and linear finite-difference techniques. Solutions are developed for 1) a constant gas compressibility factor throughout transient conditions, and 2) a variable gas compressibility factor at constant temperature dependent upon pressures encountered during transient flow. Theoretical studies are made to compare results using both approaches for pipelines operating at various constant flowing temperatures. Results show greater differences between the two methods at lower values of flowing temperature due to the more rapidly changing compressibility …

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Development Of An Elastic-Plastic Finite Element Program With The Initial Strain Approach, Vernon Dale Allen Jan 1971

Development Of An Elastic-Plastic Finite Element Program With The Initial Strain Approach, Vernon Dale Allen

Masters Theses

"A finite element method is presented for solution of plane stress and axisymmetric elastic-plastic problems employing the method of successive elastic solutions with the initial strain approach. The problem of nonconvergence of the initial strain approach for perfectly plastic problems was eliminated by expressing the Prandtl-Ruess equations entirely in terms of strain. Two examples are presented to demonstrate the validity of the method"--Abstract, page ii.

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High Temperature Compressive Creep In Mullite, Peter C. Smith Jan 1971

High Temperature Compressive Creep In Mullite, Peter C. Smith

Masters Theses

"Compressive creep measurements were made on two groups of mullites at temperatures between 1455ºC and 1520ºC. The first group consisted of commercially manufactured mullites. The second group was made up of 7 different mullite compositions spanning the alumina-silica solid solution range from 3Al₂O₃ • 2SiO₂ to 2Al₂O₃ • SiO₂ . Thermal activation energies and stress exponents were calculated for the mullites in the second group. Steady state strain rates taken at 1460ºC under loads of 100 and 110 psi varied between 1.3x10⁻⁴ in/in/hr and 15.4x10⁻⁴ in/in/hr. Activation energies were between 109 Kcal/mole and 204 Kcal/mole. Stress exponents calculated from data …

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An Age Hardening Study Of Magnesium-Thorium-Manganese Alloys, Kuldip Singh Chopra Jan 1971

An Age Hardening Study Of Magnesium-Thorium-Manganese Alloys, Kuldip Singh Chopra

Doctoral Dissertations

"The age hardening processes in Mg-3.5 wt.% Th-1.0 wt.% Mn and Mg-1.0 wt.% Th-1.0 wt.% Mn alloys have been studied by light and electron microscopy, and by electron and X-ray diffraction. At aging temperatures of 300ºC and below, G.P. zone formation rapidly hardens these alloys followed by the precipitation of disc shaped plates during averaging. During aging above 300ºC, no G.P. zones form and the disc shaped precipitate grows to very large sizes. The combined results of X-ray and electron diffraction indicate that the disc shaped precipitate has a Mg₃Cd (DO₁₉) type structure. The basal plane of the Mg₃Th discs …

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Dynamic Behavior Of Eccentrically Stiffened Plates, Charles Stuart Ferrell Jan 1971

Dynamic Behavior Of Eccentrically Stiffened Plates, Charles Stuart Ferrell

Doctoral Dissertations

"The dynamic behavior of eccentrically stiffened rectangular plates is studied by the finite element method. The addition of stiffeners to a plate structure is a common method of increasing the rigidity of the structure with a minimum of weight increase. However, this stiffened plate configuration does not easily lend itself to analysis. This study is an approach to finding a rational method by which the dynamic behavior of such a stiffened plate structure may be determined. The governing differential equations for the finite element model are derived and the stiffness and mass matrices for the plate and stiffener elements are …

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Identification Of Linear Systems With Delay Via A Learning Model, Hugh Francis Spence Jan 1971

Identification Of Linear Systems With Delay Via A Learning Model, Hugh Francis Spence

Doctoral Dissertations

"The effects of input delay on an identification scheme using a learning model are investigated. The parameter adjustment laws for the learning model are derived through Lyapunov methods similar to those used for the model reference adaptive control systems of Parks. For no measurement noise or delay mismatch between the learning model and system, the parameters are adjusted to bring the error between model and plant to zero. When there is delay mismatch between the inputs of the learning model and the unknown system, the convergence of the parameters of the learning model to those of the unknown system is …

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Surface Reactions Of Boron With Clean Tungsten Substrates, Thomas A. Flaim Jan 1971

Surface Reactions Of Boron With Clean Tungsten Substrates, Thomas A. Flaim

Doctoral Dissertations

"A model developed to predict adsorbate-induced work-function changes for thermionic emitters is shown here to apply to a more general class of electron emission phenomena and a much broader range of adsorbates. This model predicts that chemically, vapor-deposited boron will increase the work function of a clean tungsten substrate at coverages between 0 and 1 monolayer. This is the first time that a single model has been shown to predict both positive and negative work function changes for different adsorbates. The reactions of chemically, vapor-deposited (CVD) boron with clean tungsten substrates were studied using field emission microscopy (FEM) and low …

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The Effect Of Channel Errors In The Differential Pulse-Code-Modulation Transmission Of Sampled Imagery, Roger J. Arguello, Harvey R. Sellner, John A. Stuller Jan 1971

The Effect Of Channel Errors In The Differential Pulse-Code-Modulation Transmission Of Sampled Imagery, Roger J. Arguello, Harvey R. Sellner, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Presents an Analysis, Simulation, and Discussion of the Effects of Communication Errors on Four-Bit Differential Pulse-Code Modulation (DPCM) Sampled Imagery. Simulations Are Presented that Describe the Effects of Inserting Periodic "PCM Updates" in Order to Correct Communication Errors in the DPCM Transmission of Photographic Scenes that Have Been Scanned and Sampled at the Nyquist Rate. Copyright © 1971 by the Institute of Electrical and Electronics Engineers, Inc.

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Maximum-Distance Linear Codes, Gary K. Maki, James H. Tracey Jan 1971

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.

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