Engineering Commons^™

A Monte Carlo Calculation Of Neutron Reflection From Various Curved Surfaces, Charles Jack Kalter

Doctoral Dissertations

"Plane parallel neutron beams normally incident upon the curved surface of a solid reflector are studied with the Monte Carlo method. The geometries studied are cylindrical, parabolic, and hemispherical. It is shown that when the curved surface is cylindrical, a small "focusing effect" occurs in the reflected neutron beam. Parabolic and hemispherical surfaces do not show "focusing". A study of the factors which determine the spatial dependence of the reflected flux shows that the probability of emergence of a neutron, traveling a fixed distance from a point inside the reflector, depends upon the curvature of the surface. It is only …

A Study Of Early-Late Type S0-Pcm Signal Bit Synchronizers, Kuang-Cheng Hu

Masters Theses

"The steady-state phase noise performances of an absolute value type and a squaring loop type of early-late gate S0-PCM signal bit synchronizers are developed using the Fokker-Planck method. The results are compared on the basis of the performance of two configurations with equal loop bandwidth at each input signal-to-noise ratio R_s. The probabilities of bit-detection error of the two configurations are compared. These comparisons are made as a function of R_s. The absolute value type of early-late gate S0-PCM signal bit synchronizater yields better performance than that of the squaring loop type of early-late gate S0-PCM …

Final Sintering Of Cr₂O₃ With Minor Additions Of Mgo And Sintering Of Mgo With Minor Additions Of Cr₂O₃, Gordon E. Jungquist

Masters Theses

"The effect of oxygen activity on the sintering of Cr₂O₃ with minor additions of MgO, and of MgO with minor additions of Cr₂O₃ at 1600ºC was investigated. A peak density (99.4% of theoretical) was obtained for high purity Cr₂O₃ by maintaining the equilibrium oxygen partial pressure needed to maintain the Cr₂O₃ phase. The addition of 0.1 wt. % MgO increased the sintered density at the same oxygen pressure to 99.8%. Further MgO additions decreased the density. The density of pure MgO was independent of the P_O₂ over the range investigated. Addition of Cr₂O₃ to MgO decreased the density at …

Ladder Network Transfer Function Characteristics, Thomtavanit Hatayodom

Masters Theses

"This thesis investigates the network characteristics and synthesis procedure previously developed. As a result of this investigation, location of the absolute minimum values of Navot's method is determined; a procedure is given for obtaining more desirable component values for a given ladder network without changing its transfer function; a procedure is given for obtaining the source location in a ladder network that yields the desired numerator degree of its transfer function; and a computer program for helping to obtain the above result is presented"--Abstract, page ii.

Normal Mode Method Applied To The Transient Longitudinal Vibrations Of A Finite Rod With Material Damping And Viscoelastic Dispersion, David Arthur Levene

Masters Theses

"Longitudinal vibrations of a finite rod with material damping and frequency dependent material properties are examined. The normal mode method is used to investigate the transient response of a rod which is free to move in the longitudinal direction and is subjected to a transient longitudinal loading condition at one end. The equations of motion are derived and solved using both the differential equations approach and the energy methods approach of the normal mode method. The effects of material damping and frequency dependent material properties are considered by formulating the stress-strain relation for the material such that the modulus of …

Radiant Interchange In A Non-Isothermal Rectangular Cavity, Tilak Raj Sawheny

Masters Theses

"Radiant interchange between non-isothermal, gray diffuse surfaces with non-uniform radiosity has been determined for a rectangular cavity. Temperature distribution and heat flux as thermal specifications for the parallel surfaces of the cavity have been considered separately. Ambarzumian's method has been used for the first time to solve a radiant interchange problem. According to the method, the integral equation for the radiosity is first transformed into an integro-differential equation and then into a system of ordinary differential equations. Initial conditions required to solve the differential equations are the H-functions. The H-functions represent the radiosity at the edge of the cavity for …

Design Of A Semi-Automatic Transmission, Yogendra Prahladray Buch

Masters Theses

"Design of a semi-automatic four-speed transmission for automotive engines with moderate horsepower is described. The basic configuration consists of main and countershafts and five pairs of constant-mesh gears. Engine torque is transmitted through an input gear pair to the countershaft, and finally to the output shaft through a selected output gear pair. Selection is accomplished by engaging one of five hydraulically operated clutches located on the countershaft. Engagement fixes the desired gear to the countershaft and engine torque is then transmitted to the mating gear, which is fixed to the output shaft. Fourth speed is obtained by coupling the input …

The Integrated Planning Method Of Project Planning, Development And Implementation, Joseph Frank Lynch

Masters Theses

"Present comprehensive planning endeavors lack a consistent methodology which will produce realistic, useable results. The validity of this statement should be obvious after one has read Miller's "Evaluation of City and Region Planning Techniques." This paper contains a methodology, "The Integrated Planning Method," which will go a long way toward correcting this gross inadequacy that planners presently encounter in directing planning efforts. Two government developed planning and analysis procedures that, up until this time have been applied almost exclusively to hardware systems, have been combined into one integrated planning methodology that will provide not only meaningful and rigorous definition 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.

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 …

The Thermal Contact Resistance Of Lubricant Films In Vacuum, Garry A. Heizer

Masters Theses

"This paper presents the results of an experimental investigation on the thermal contact resistance of lubricant films and bare interfaces. The apparatus and procedure used in the determination of these resistances are described. Twelve series of tests were performed to evaluate the effects of temperature and contact pressure on the thermal resistance of lubricant films. Variations of thermal contact resistance with temperature and contact pressure for four lubricants and for bare interfaces are presented graphically. The thermal resistances of the four lubricants tested in vacuum conditions: lithium grease, graphite grease, molykote grease, and silicone lubricant, were found to lie in …

A Statistical Hydrologic Simulation Model, Ronald L. Wycoff

Masters Theses

"Simulation of a physical system requires knowledge of all components of the system and their interactions. A probabilistic simulation model of a hydrologic system is developed from short term continuous, sychronized rainfall-runoff records. The individual components of the system area the time between and duration of storms, the depth of rain occurring in each time period of the storm, precipitation excess relations, and the watersheds unit hydrograph. The available data is used to define or develop the probabilistic models involved. The only nonprobabilistic model employed is the watersheds unit hydrograph. It is found that the time between and duration of …

An Investigation Of A Bistable Oscillator Used In A Phase Modulated Control Circuit, Yu-Fang Yen

Masters Theses

"A primary component in the investigation of phase modulated control systems is bistable oscillator which converts a constant oscillation signal to control the system. The oscillator is feedback type that utilizes a feedback capacitance and resistance in each feedback path to change its frequency. The theoretical behavior of bistable oscillator was investigated and the non-dimensional results were set for convenience in determining the oscillation period. The control circuit which based on the oscillator was also presented a form of suitable circuit for direct application to practical control problems"--Abstract, page ii.

Activation Volumes Of Carbon Diffusion In F.C.C. Iron-Nickel Alloys, James Raymond Keiser

Doctoral Dissertations

"The disaccommodation technique was used to determine the activation volume of carbon diffusion, ΔV, in six fcc iron-nickel alloys. Measurements were made at temperatures ranging from 68ºC to 90ºC and pressures up to six kilobars on samples having a nickel content between 31 and 63 at. %. A maximum activation volume of 3.9 cm³/mole was found at 34 at. % nickel. The compositional dependence of ΔV is satisfactorily reproduced by a magnetic energy continuum model in which it is assumed that the activation free energy of diffusion is essentially ferromagnetic in origin "--Abstract, page iii.

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 …

A Comparative Study Of Experimental And Computed Compressibility Factors Of Methane - Nitrogen - Helium System, Promod Kumar Taneja

Masters Theses

"The volumetric data for methane, nitrogen, and helium mixtures have been determined experimentally at low temperatures (60ºF to -30ºF) over a pressure range of 1000 to 5000 psig. An attempt has been made to show that the extension of standard techniques viz, "The Law of Corresponding States" for predicting the compressibility factors of pure hydrocarbons and hydrocarbon mixtures is not adequate for mixtures containing even very small amounts of helium. The deviation from the computed compressibility factors is found to be maximum at low temperatures and high pressures (up to 22%) for the mixtures studied"--Abstract, page ii.

Shop Level Maintenance Of Inertial Platforms Without A Surveyed Site, Max E. Bott

Masters Theses

"The initial installation of a rotary tilt table for an aircraft inertial navigation system test facility includes accurately aligning the rotary tilt table to local level and true north coordinates. The survey techniques presently employed are an encumbrance during installation and complicate remote deployment. The objective of this thesis is to determine if an inertial platform or platforms can practically be used to replace the role of the survey techniques in the rotary tilt table alignment. The construction, capability and operation of a rotary tilt table are reviewed. The tests necessary to test and calibrate an inertial platform are outlined, …

Two Component Heat Pipe, Surapol Chandsawangbhuvana

Masters Theses

"A two component heat pipe with water and ethanol as the working fluid was investigated at different angles of inclination and various ethanol concentration for two power loads. The heat pipe was 15 inches long and 0.75 inches in diameter with a 100 mesh stainless steel screen wick. The wall and the vapor temperatures were measured at different stations along the length of the heat pipe by copper-constantan thermocouples. The results were used to evaluate an existing model which includes the constraint of thermodynamic phase equilibrium of the solution on the governing equations. Based on the measured pressure and temperature …

Digested Sludge Dewatering On Drying Beds Under Controlled Environmental Conditions, Daniel James Harris

Masters Theses

"The dewatering characteristics of anaerobically digested primary and activated sludge were investigated under eight selected combinations of laboratory controlled air temperature and relative humidity using three open, drained model beds, as well as a closed, drained and an open, nondrained bed. The evaporation rate from a free water surface was also determined. Moisture content, drainage, evaporative weight loss, and sludge surface recession were measured and recorded periodically throughout the two week period of each of the eight experiments. Relationships were shown to exist between sludge moisture content, evaporation rate from a free water surface, and the parameters 6T (the difference …

Development Of A Set Of Optimum Synchronization Codes For A Unique Decoder Mechanization, Irv D. Siegel

Masters Theses

"Synchronization requirements are specified for and a unique decoder mechanization is associated with a particular communication system. Optimum synchronization codes, defined as codes which are the least susceptible to false synchronization indications, are sought. Existing sets of optimum codes are investigated for applicability. This Thesis shows how these sets were developed from selected criteria and demonstrates why their theoretical nature produces unsatisfactory results in the present application wherein all parameters are known. A computer program was written to examine code pattern performance in the specified decoder under actual operating conditions. From an analysis of the results, a recommended set of …

A Method For Studying Sequential Faults On A Three Phase Distribution Transformer, Shashi Kant Pandey

Masters Theses

"A method has been presented for studying sequential faults on opposite sides of a three-phase distribution transformer using the theory of symmetrical components and Alpha, Beta, and Zero components of three-phase systems. The effect of the faults on the distribution system has also been analyzed and improvements in the protection scheme suggested. The sequential faults occurred, one after the other, on the distribution system of the Central Electric Power Cooperative of Jefferson City in the state of Missouri resulting in a double unbalanced fault condition. The data used in the example problem has been supplied through the courtesy of the …

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 …

The Skid Resistance Of Asphaltic Pavements Using Glass Aggregates, Michael Vaughn Korth

Masters Theses

"The disposal of the glass portion of solid waste is an ever-growing problem in the U.S. and recycling has been suggested as a possible solution. In order to find new uses for waste glass, investigations have been conducted to determine if the glass could be used as an aggregate in bituminous concrete mixtures. As part of the overall investigation, this study was concerned with investigating the skid resistance properties of the glass aggregate mixtures, called glasphalt. The objectives were to compare the skid resistance of various bituminous mixtures using aggregate combinations ranging from all glass to all conventional aggregate and …

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 …

An Investigation Of Stress In The Monowall Construction System Subjected To Racking Loads, Louis Alex Kuhlmann

Masters Theses

"Several methods of analysis were employed to investigate the stress conditions of concrete block built in the MONOWALL Construction System, when subjected to racking loads. MONOWALL is a technique of assembling blocks with adhesive rather than conventional portland cement mortar. The analyses used in this study included strain gages on full-scale walls, photoelastic models, and a mathematical solution. Each method of analysis is reported separately in detail and the results compared to each other"--Abstract, page ii.

A Digital Computer Simulation Of A Rural Two-Lane Highway, D. Jay Frankenfield

Masters Theses

"The traffic flow model developed in this study is a digital computer simulation utilizing the technique of periodic scanning to move the vehicles through a series of unit blocks. The model simulates traffic flow on a rural two-lane highway by assuming a straight and level road and incorporating sight distance restrictions and no-passing zones to simulate the effect of limited sight distance. By utilizing various "passing rules" to initiate the passing maneuver, three general topics were investigated. This study investigated the use of 1000 ADT as a criterion for yellow line striping no-passing by using the computer simulation to determine …

Design And Preliminary Testing Of A Thermomechanical Rock Fragmentation Apparatus, Gary Earl Fenton

Masters Theses

"The design characteristics of equipment to thermally weaken and mechanically fragment hard rock were developed and the apparatus constructed. An initial investigation of thermo-mechanical fragmentation was conducted on Missouri red granite. The particles from the fragmentation tests were sized and this analysis was used in the Rittinger theory to calculate surface area breakage energy. It was found that the application of thermal energy could reduce the surface area breakage energy per unit volume of material removed by as much as 41 percent. The use of kerfs in the rock increased the amount of material removed and permitted larger particles to …

Structure And Properties Of Silver Borate Glasses, Edward Nashed Boulos

Doctoral Dissertations

"Clear glasses form in the system Ag₂O-B₂O₃ up to about 35 mol.% (65 wt.%) Ag₂O. Infrared absorption, thermal expansion and density data indicated an analogy to the Na₂O-B₂O₃ system. Pentaborate-triborate group pairs appear to be formed upon the addition of Ag₂O to B₂O₃ up to 20 mol.% Ag₂O and diborate groups from 20 to 33 mol.% Ag₂O. This interpretation is supported by the comparison of the infrared absorption spectra of quenched and crystallized glasses. One crystallization product ,Ag₂O.4B₂O₃, has been identified previously. A new compound starts to appear at 28 mol.% Ag₂O. Silver is generally present as a network modifier …

Response Surface Study Of A Characteristic Chemical Plant, John Thomas Mason Iii

Doctoral Dissertations

"Study of the return on investment response surface of a characteristic chemical plant indicates unimodality in the valid region, but the optimum design condition with this response surface is strongly affected by the correlation used for the investment. The method used for the design of this type of chemical plant incorporates the use of a simulation routine for preliminary estimates"--Abstract, page ii.

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 …