Engineering Commons^™

The Development Of The Sonic Pulse Technique And Its Comparison With The Conventional Static Method For Determining The Elastic Moduli Of Rock, James Harold Deatherage

Masters Theses

"The determination of the elastic moduli of rock has long been a problem to the geophysicist, mining engineer and the civil engineer. There is a considerable amount of literature on determining Young's modulus by the sonic pulse technique. However, the use of this technique to determine the three elastic constants, Young's modulus, shear modulus, and Poisson's ratio from measurements of both the longitudinal and shear wave velocities presents some difficulties, especially in the method of accurately determining the shear wave velocities.

In this thesis, what is believed to be a new method of measuring shear wave velocities in the laboratory …

Decarboxylation Of Malonic Acid In Aqueous Solutions, Ramesh Natwarlal Gujarathi

Masters Theses

"The rate of decarboxylation of malonic acid in aqueous solutions was studied over a range of concentrations, pH's, and temperatures. The catalytic effect of various divalent metallic ions was also studied at a pH of 0.3. these studies did not support a truly unimolecular decomposition as the experimental order was found to be slightly greater than one. An empirical relation for the rate of decarboxylation was formulated in which the undissociated malonic acid and the monovalent malonate ion were the reactive species.

A possible mechanism of decarboxylation due to solvent activation was postulated. No pronounced catalytic effect due to the …

Mass Transfer In Droplets With Turbulent Internal Circulation - Mathematical Description, Jayantilal Mohanbhai Patel

Masters Theses

"This investigation was carried out to check the accuracy of the eigenvalues, λ_n, calculated by Wellek and Skelland, using some method other than the Rayleigh-Ritz technique and also, to determine the coefficients, B_n in series solution, which were not calculated before.
The eigenvalues were obtained by trial and error procedure using the standard Runge-Kutta method. The coefficients B_n were obtained by using eigenvalues. By using this information the fractional extraction was calculated as a function of droplet contact time.

The Wellek-Skelland modification was also solved by finite difference technique to compute fraction extracted as a function …

An Ac Method Of Measuring The Conductivity Of Dielectric Liquids., Henry E. Fischer

Masters Theses

"The problem undertaken in this thesis is the presentation of a method of measuring the conductivity of dielectric liquids in which the liquid is used as the parallel tank circuit of a modified Wien-bridge oscillator. The main advantage of this method is that the frequency of the voltage applied to the liquid can be varied by simply varying the oscillator frequency. This allows the selection of a frequency which is best suited to the liquid in regard to polarization and relaxation time.

An oscillator was designed, built and used in the laboratory to measure the conductivity of the dielectric liquids …

A Study Of Stress Distribution And Measurement Of Axial Strain Around A Pilot Hole During Overboring, Varakantham Sreedhar Reddy

Masters Theses

"Stress distribution around a pilot hole during overcoring was investigated. A study of axial strain on the borehole surface was undertaken. Two-dimensional epoxy resin models were prepared and stress frozen in a centrifuge. The stress-frozen models were examined under a direct-viewing polariscope. The magnitude of axial strain and the effect of strain relaxation on the pilot hole were measured on blocks of brittle materials. Factors contributing to discing of core during the overcoring operation were investigated and a mechanism of failure postulated. The loading conditions simulating in situ, core and bit pressures were applied individually to the brittle models and …

Space-Charge Effects As Determined By Initial-Field Conditions, Tsing-Yih Wang

Masters Theses

"A method for calculating the current density passing between two parallel plane electrodes for different values of positive charges as a function of " field at the emitter to field for no charge ratio " is presented.
The problem of the potential distribution between the electrodes has been solved for one particular case in which the positive charges are assumed to be proportional to the field at the emitter. The expressions for the electric field, the velocity of charges, and the charge density as a function of the potential are also presented and plotted as a function of the distance. …

A Photoelastic Study Of The Stresses In A Deep Beam Using Partial Mirrors For Isochromatic Fringe Sharpening And Fringe Multiplication, Edward M. Raney

Masters Theses

"This paper is a photoelastic investigation of the stresses in a deep beam using partial mirrors to obtain isocromatic fringe sharpening and fringe multiplication. This method may be of particular value in photoelastic work for obtaining full field fringe multiplication and fringe sharpening for models which exhibit low fringe orders.

The photoelastic model used in this investigation is a deep beam with a length to depth ratio of one. A uniform load is applied over the center one-half of the beam. The beam is supported by two uniform loads distributed over a length of one-quarter the span.

A first approximation …

The Effect Of Structure On The Consolidation Characteristics Of A Clay Soil, Dale E. Sukow

Masters Theses

"This paper reports the results of an investigation conducted to establish the effect of structure on the consolidation characteristics of a clay soil. Soil structure was caused to form in the soil by the addition of electrolytes to flocculate and disperse the clay fraction of the soil.

Consolidation tests were performed on specimens of the treated soil prepared at moisture contents well above the liquid limit of the soil. The consolidation data from these tests are evaluated and comparisons are made to relate the influence of structure to the consolidation characteristics of the treated soil.

The influence of structure on …

Analysis Of Time-Varying Linear Multipole Filters With Sampled Nonstationary Random Inputs, Ming-Chwan Chow

Masters Theses

"In this thesis an analytical method is developed to determine an optimum time-varying linear filter in order to satisfy the following specifications. The filters are of sampled data multipole form with n inputs and m outputs. The signal of each input is a member of a nonstationary random process, and the signal is corrupted by stationary noise.

The statistical optimization theory developed by Wiener is extended to a linear time- varying filter with nonstationary input. Correlation functions are defined for nonstationary ensembles. The mean- square error is calculated in terms of these correlation functions. By minimization of the mean-square error, …

A Study Of Shear Failures In Footing, Fred V. Cole

Masters Theses

"The purpose of this investigation was to conduct a model study of the basic mechanism of failure in shear of reinforced concrete footings through the use of plaster models.

Sixty-nine models were constructed and loaded to failure on a foundation of sand using various combinations of size and depth of model and column size. Load - deformation data and failure loads were recorded.

It was determined that model studies are a feasible procedure to analyse the mechanism of failure in footings. The perimeter of the loaded area was found to be the critical section in determining the ultimate shearing strength …

An Application Of The Variable Gradient Method Of Generating Liapunov Functions To Discrete Systems, Henry N. Peterson

Masters Theses

"The variable gradient method of generating Liapunov functions has been used only for continuous systems. This thesis presents an application of the variable gradient method to non-linear sampled data control systems.
Certain modifications to the variable gradient method are developed and several examples are presented which demonstrate the application. An attempt was made to synthesize the control system parameters, but due to the complexity of the ΔV functions, the synthesis in general cannot easily be obtained . To circumvent the problem of determining if the ΔV functions are negative definite, a set of computer programs were written to determine a …

A Periodic Dielectric Rod Antenna, Robert C. Peirson

Masters Theses

"The periodic dielectric rod antenna structure under consideration consists of identical dielectric rod sections of radius a meters situated on a common axis. These sections are of length 1₁ meters and are separated in free space by distance 1₂ meters.

Field analysis employing Floquet's theorem, in terms of the exemplary TM₀₁ circular mode, gives expressions for the various field components and an eigenvalue equation. Digital solution of this eigenvalue equation establishes the location of propagation bands as a function of frequency. Such bands are characteristic of any periodic wave guiding structure."--Abstract, page ii.

A Probability Density Analyzer, Thomas K. Bohley

Masters Theses

"A means is presented by which the probability density of statistical signals may be determined experimentally. The design and construction of an electronic test instrument to measure probability density is discussed. Operating instructions and circuit diagrams are also included"--Abstract, page ii.

Modal Characteristics Of A Vibrating Truss, Edd Leighman Ghent Jr.

Masters Theses

"In this thesis, a complete technique is presented for the vibration analysis of any planar structure which can be classified in the broad category of trusses or frames. Although a theoretical backdrop is included for the' sake of completeness, the intent is to provide a technique that is readily adapted to computer usage and can be handled with a minimum of confusion or misunderstanding.

The problem is solved by the use of a displacement technique wherein the inertia and stiffness properties of a structure are calculated by superimposing the contributions of each component of the structure. The calculation of these …

A Study Of Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Girish T. Dalal

Masters Theses

"A microinterferometric method was used to study the effect of solute concentration on the diffusion coefficient in polymer solutions and also to determine the effect of polymer concentration on the diffusion coefficient. The polyacrylonitrile-dimethylformamide system was used as a means of determining the accuracy of the experimental apparatus and procedure. The non-ionic, water soluble polymer, hydroxyethyl cellulose (commercially known as Natrosol), was used to study this effect with urea and D-glucose as the solutes.

The results obtained for the polyacrylonitrile-dimethylformamide system were in close agreement with the results obtained by Secor, which meant that the experimental technique is accurate enough …

Analog Simulation Of The Voigt Solid, Richard F. Pohl

Masters Theses

"A method of reducing a mixed partial differential equation with boundary conditions to a form suitable for programming on the analog computer is developed. Presented along with the computer program set up to be used on the EAI TR-48 analog computer is a systematic check procedure to indicate possible computer malfunctions and programming errors. The results of the computer simulation are presented and supported with observed data"--Abstract, page ii.

Location Of Maximum Moments In A Continuous Two Span Beam Due To Moving Loads, Thomas Houng-Yn Yang

Masters Theses

"The objective of this investigation is to determine the positioning of vehicle wheels so as to cause maximum positive and negative moments in a two span continuous girder. Several variables are considered, namely, the ratio of loads to each other, the distance between wheels, and ratio of one span length to the other. The necessary equations are derived and the results, after being programmed on a computer, are shown in a series of curves.

These curves serve as a tool for the designer, enabling him to arrive at design moments by simple substitution in the appropriate moment expression, within the …

An Algorithm For The Synthesis Of Nand Logic Networks Using A Diagrammatic Approach, Donald Robert Nelson

Masters Theses

"A diagrammatic approach is presented for the synthesis of multilevel NAND networks realizing combinational logic expressions. The network synthesized is restricted to only uncomplemented inputs. The synthesis algorithm involves the determination of minimum sum of products and product of sums expressions for a Boolean function, construction of an α-ß diagram from these expressions followed by implementation with NAND gates directly from the diagram. The resulting network is a minimal or near minimal NAND gate realization of the given function. The algorithm is applicable to completely or incompletely specified Boolean functions and is extended to include NOR synthesis"--Abstract, page 2.

A Study Of The Effect Of A Square Cutout On The Moment Distribution In A Simply Supported Rectangular Plate Under Normal Concentrated Load By The Moiré Fringe Method, Taher F. Raja

Masters Theses

"Plexiglass models were used to produce Moiré fringes for two different geometrical shapes. The moments in the case of a simply supported rectangular plate with a normal concentrated load were found using the Moiré fringes which directly give the gradients at all points of the surface of the model. The variation of the moments due to a square cutout was also studied by this method. As a check for the experimental method, the analytical solution was presented for the plate without a cut-out. The Moiré method yields moments to an accuracy of 3 to 15 percent, however, care must be …

A Nonlinear Sampled Data Feedback Control System Employing Pulsed Thrust Position Control, John D. Corrigan

Masters Theses

"This thesis shows that reaction jet thrust pulses, each of constant amplitude and time duration, in conjunction with sampled data error information can provide satisfactory position and/or attitude control for space vehicles.

Incremental phase-plane analysis of the system yields a technique for determining system response and suggests a means of compensation. Control system response for the vehicle under the influence of external forces is shown to be satisfactory by digital computer simulation"--Abstract, page ii.

A Method For Approximating A Specified Impulsive Response, Charles A. Gross

Masters Theses

"Given a system's time response, y(t), to a unit impulse, a method is presented by which an approximating function y*(t) may be determined. It is inherent in the method that the transform function Y*(s) is rational. The poles of the approximating function are found from the coefficients of a difference equation, which is made to fit the given data in a least mean square error sense. The zeros are determined by a procedure based on the fact that at a given time the given function and its approximate derivatives are known. Accuracy and implementation of the method are investigated primarily …

Phase And Amplitude Distributions Of An Unsymmetrically Fed Ground Plane Aperture, Leslie Blumberg

Masters Theses

"An anechoic chamber for use in the B-12 KHz range was designed and built for the purpose of obtaining the far field patterns of antennas and radiation systems. This chamber was evaluated and compared with various types of anechoic chambers from the standpoint of their "room performance."

The anechoic chamber is essentially a room lined with absorbing material, effective at microwave frequencies. The purpose of the absorbing material within the room is to present the reflection of the energy incident upon the walls of the room.

Measurements of the far field radiation pattern of an aperture in a ground plane, …

The Plastic Behavior Of Reinforced Concrete Beams With Varying Percentages Of Reinforcing Steel Symmetrically Placed, J. Leroy Hulsey

Masters Theses

"The purpose of this study is to determine the limitations of the plastic behavior of reinforced concrete beams with varying percentages of high strength steel (ASTM-A-432) cutoff in the compression region d distance beyond the point of inflection. Comparison was made with the derived equations.

Steel was placed symmetrically in order to obtain like action at critical sections. The members tested were of a propped beam nature having a total clear span of 5'6" with a 6" overhang on one end and 1'6" overhang on the other. Concentrated loads were applied so as to obtain midspan loading and fixed end …

Some Effects Of Selected Biodegradable Detergents On The Aeration Of Water And Activated Sludge, Donald Ernest Modesitt

Masters Theses

"The purpose of this study was to determine what effects the presence of selected biodegradable detergents have on the aeration of water and the activated sludge process for aerobic wastewater treatment. The detergents studied were LAS #1, Alfol, and Nalkylene. It was of particular interest to determine if these detergents decreased the oxygen absorptive capacities of water and wastewater. If detrimental effects were produced by the detergents it was then desired to determine if these effects were serious enough to create problems with aerobic wastewater treatment and aeration in receiving bodies of water.

A two liter volume of the liquids …

The Effect Of Combined Torsional And Bending Loads On A Channel Beam With One End Restrained From Warping, David M. Schaeffer

Masters Theses

"Channel beams have been designed with the main purpose of giving large resistance to bending while the torsional strengths are known to be relatively small. In this experiment, a cantilevered channel beam was loaded with a concentrated load at the free end, first through the experimentally determined shear center and then through the centroid of the cross section. For each loading condition, the strains were measured with the aid of SR-4 strain gages placed at intervals along the length of the beam. With the aid of a computer, the strains were converted into longitudinal stresses and these stresses were compared …

The Effect Of Non-Linearity On A Frequency-Modulated Wave, Tzu-Tien Hung

Masters Theses

"A method is presented for finding the effect of a nonlinear characteristic of a device on a wave which is frequency modulated by only one sinusoidal modulating wave. The distortion in the output has been found by passing a frequency-modulated wave (which is represented by a summation expression for the spectrum components) through a non-linear circuit having a Fourier series represention of its Characteristic. Two cases have been considered: (1) a nonlinear output-input characteristic, and (2) a non-linear amplitude-frequency characteristic"--Abstract, page ii.

Analysis Charts For Single And Multi-Span Gabled Frames, John (Chung-Su) Ma

Masters Theses

"A method for analyzing single and multi-span gabled frames using analysis charts is presented. This method requires considerably fewer computations than methods previously used (such as the moment distribution and slope-deflection methods). Analysis charts are presented for single gabled frames having fixed or pinned ends at ground level, and charts are also presented which can be used to efficiently analyze multi-gabled frames.

The data for the analysis charts were obtained using matrix techniques in conjunction with the digital computer. These techniques are described"--Abstract, page ii.

The Anodic Oxidation Of Maleic Acid, Larry D. Gilmartin

Masters Theses

"The purpose of this investigation was to determine the mechanism of the anodic oxidation of maleic acid on platinized-platinum electrodes at 80⁰C. Current density-potential studies were conducted varying the parameters of maleic acid concentration and pH. The faradaic efficiency of the oxidation of maleic acid to yield CO₂ was determined. The effect of temperature on current density was also studied to determine the activation energy for the reaction. The oxidation of maleic acid occurred only in acidic solutions. The faradaic efficiency was found to be approximately 97 ± 5 per cent. A linear Tafel region was found which had a …

Analysis Of Sand Asphalt Mixtures, Maurice A. Sayegh

Masters Theses

"The objective or this investigation was to determine the optimum percent of asphalt which should be added to the sand asphalt mixture. Also the effects of filler on the properties or the sand-asphalt mixture were evaluated.

The variables in this study were mineral filler, asphalt cement, and asphalt content. The sand used in this study was sub-rounded, and uniformly graded. The asphalt was asphalt cement with two different penetrations, one of 85-100 penetration grade and the other of 120-150 penetration grade.

Three different groups of mixtures of sand-asphalt were prepared. The first group consisted of adding 85-100 penetration asphalt to …

The Anodic Dissolution Of Magnesium In Aqueous Solutions, Chen-I Lu

Masters Theses

"The anodic dissolution of magnesium was studied in MgCl₂-KC1 and MgBr₂-KBr mixtures at 25, 40, and 55 °C. The parameters of the study were current density, concentration of magnesium ion, and temperature. The concentration of magnesium ions was varied from 0.001 to 1 N holding the ionic strength constant at 1.5. The weight loss of magnesium from the electrode during electrolysis was determined by weighing the electrode both before and after electrolysis. The current was measured with a sensitive milliammeter. The range of the current densities was varied from 0.001 to 0.1 amps·cm^-2. The …