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Estimating Bench Design Parameters For Open-Cut Excavation, Rajni K. Gandhi

Masters Theses

"There are no direct relationships available that provide a basis for bench design of multiple-bench, open-cut earth excavations in competent materials when power shovels are employed. This study was undertaken to determine if mathematical design expressions could be developed when the production rate, material's properties, and equipment operating characteristics were known.

It was found that all bench dimensions were a function of the bench height, which in turn was controlled by the required rate of production. The investigation revealed that suitable relationships could be developed to guide in the control of bank stability, choice of shovel capacity, determination of the …

The Anodic Dissolution And Disintegration Of Gallium And Aluminum And The Initial Valency Of The Ions Entering Aqueous Solutions., Kenneth Anderson Poush

Masters Theses

Gallium dissolved very slowly in dilute acids like HC1, H₂SO₄and HCIO₄. The rate was substantially accelerated if the metal was connected with a platinum electrode in the same solution. From the volume of the hydrogen developed the trivalency of gallium ions going into solution was calculated. This same ionic charge was obtained from coulometric measurements using gallium-amalgam as the anode. The initial ionic charge of aluminum dissolving from an aluminum amalgam anode was evidenced as being plus three by coulometric measurements.

Gallium and aluminum anodes were found to partially disintegrate while the current flowed. …

Optimalization By Peak-Holding, Curtis W. Dodd

Masters Theses

"The problem presented is a study of the peak-holding method of optimalization. This method applies to a system that has an extremum.

After describing how the complete system, consisting of the controller and the controlled system, works; variations in the controller are presented. These variations are changes in the final stage of the controller, the servo. A phase-plane analysis shows how the output of the controlled system varies with its rate of change. Limitations are presented which tell why the system cannot be kept at its peak value at all times. Finally an analog simulation is used to study the …

Real Time Testing With A Time Scaled Analog Computer., Wayne F. Balsman

Masters Theses

"A present limitation to the testing of a physical subsystem within an analog simulation is that the analog computer must compute in real time. If it is necessary to time scale the simulation of the complete system, a physical subsystem of the complete subsystem may not be tested within the simulation. Therefore, a means of changing the time scale of the analog signal is needed to test a physical subsystem within a time scaled analog computer simulation.

In this thesis a means of time conversion by sampling the analog signal at one rate, storing the samples, and reading the samples …

Solid-Phase Welding Of Nodular Iron To Low Carbon Steel., Scott H. Carriere

Masters Theses

“This paper presents an experimental investigation of the possibility of using solid-phase welding to join nodular iron to low carbon steel. Included is a review of available literature on solid-phase welding, tracing its origin from early Egypt to the present day. There was no previously reported work found on the welding of nodular iron to steel.

Experiments were performed to determine what temperature-pressure combination gave the greatest ultimate tensile strength These experiments resulted in the best welds being produced with an end load of 7000 pounds (35.700 psi) on a half inch diameter sample. The majority of these welds proved …

A Study On Estimating Parameters Restricted By Linear Inequalities, William Lawrence May

Masters Theses

“A comparison of two methods for estimating parameters restricted by linear inequalities in linear statistical models was made.

The first method consisted of finding the least squares estimates of the parameters disregarding the restrictions, and then forcing those parameters that were outside of their allowable ranges to the nearest endpoints of those ranges.

The second method made use of quadratic programming to minimize the same sum of squares that the first method minimized while keeping the parameters inside or at the endpoints of their allowable ranges.

The quadratic programming gave better estimates of the parameters in the sense that the …

Separation Of Cationic And Colloidal Fractions Of Radioactive Fission Elements By Electrodialysis., Ronald Dean Mitchell

Masters Theses

"The rapid increase in radioisotope applicat i ons necessitates improved technology for separation and purification of the fission product elements. Electrodialysis techniques employing Permutit anion exchange membranes (3148) and cation exchange membranes (3142) were used to separate strontium from cesium and to fractionate cerium from promethium. The methods were based upon organic complex formations in basic solution.

Separations of radio strontium and radio cesium were affected with both anion and cation exchange membranes in a three-cell electro dialyzer with EDTA as a chelating agent at a pH of 11.0o Fractionation of radiocerium and radio promethium were affected with anion exchange …

Investigation Of The Effect Of The Wall Thickness On The Residual Stresses Developed In Thick Wall Cylinders Due To Water Quenching From The Outside Surface., Ghanshyam Chandubhai Patel

Masters Theses

"This investigation has been made to determine the residual stresses in thick wall cylinders by the use of strain gages.

The cylinders were quenched from their outer surface i n water from a temperature of 1000°F, and the resulting residual stresses were determined by Sachs boring-out method. The effect of the wall thickness of the cylinders on the residual stresses and the error developed due to the boring operation were discussed"--Abstract, p. ii

Densification Studies Of Three-Component Refractory Grog Systems., Jerome Dale Patterson

Masters Theses

"The bulk density and crushing strength properties of three-component refractory grog systems that were formed by mechanical impact or by mechanical vibration were determined.

Aqueous alkali silicate solutions of various types, concentrations, and amounts were investigated as room temperature binders for these grog systems. Compositions having maximum bulk densities were determined for each of six different three-component refractory grog systems. The densification rate curves for systems formed by mechanical impact were determined"--Abstract, p. ii

The Effects Of Surface Flaw Density And Configuration On Fracture Stresses Of A Triaxial Porcelain., William H. Daniels

Masters Theses

"The fracture behavior of a model brittle solid containing artificial surface flaws was studied. An industrial ceramic porcelain body was employed as the model brittle material. Sample groups of specimens containing 6, 11, 24, 49,. and 90 sharp surface notches uniformly distributed over a four inch length were broken under pure bending. The fracture data we-re compared to those of an identically treated control group containing no artificial flaws.

The mean strengths of the two groups of lowest flaw density were identical, both being significantly less than that for the control group. Further increases in flaw density resulted in increased …

A Study Of A Method For Selecting The Best Of Two Or More Mathematical Models, August J. Garver

Masters Theses

"A method for selecting the best in some sense of two or more mathematical models is investigated in this study. The method is that of using part of the data to estimate parameters and using the resulting equation to predict the additional data which are then compared with the existing data not used in estimating the parameters. In particular the effects produced on the method by the number and location of points used in estimating the parameters and the criterion for determining the best fit are investigated. It was concluded from the results of an empirical investigation that the success …

The Electrical Analogy Of Critical Speed For The Transverse Vibrations Of A Shaft With One, Two And Three Masses, Ashok Z. Patel

Masters Theses

"The object of this thesis is to determine the critical speed of a shaft by an electrical analogy. The shaft considered is of constant diameter and is simply supported at the ends by fixing it in self aligning bearings. The weight of the shaft is assumed to be proportionally distributed in the attached masses.

The original system is first of all converted to an equivalent simple spiring mass system by calculating the influence coefficients and hence frcan these determining the spring constants. The spring mass system obtained is then converted to an equivalent electrical circuit.

A sine-square wave frequency generator …

Solid Solubility Of Sodium Oxide In Tricalcium Aluminate, Joel A. Conwicke

Masters Theses

"The tie line connecting the compounds 3CaO·Al₂O₃ and Na₂O·8CaO·3Al₂O₃ in the ternary system CaO-Al₂O₃-Na₂O was studied at 1250° Celsius.

It was determined that Na₂O can exist in crystalline solution with 3CaO·Al₂O₃ in percentages of about 2.3% or less without any apparent change in the structure of 3CaO·Al₂O₃. X-ray diffraction peaks in the back-reflection region shifted to lower d-spacing values on increasing Na₂O contents.

At a Na₂O content of about 2.7%, each major x-ray …

A Study Of The Separation Of A Mixture Of Carbon Dioxide And Hydrogen By Means Of An Orifice., Larry Gene Bauer

Masters Theses

"The purpose of the investigation was an attempt to verify a statement made by Partridge in an effort to discover a new method of separating gaseous mixtures. Partridge stated that when a constant pressure is applied on two gases of different specific gravity, a larger volume of the l igl1ter gas is forced through the orifice. Orifices of 1.016, 0.319, and 0.222 millimeter in diameter were used in the course of the investigation.

It was found that with the apparatus used in the research endeavor, no separation of the mixture of hydrogen and carbon dioxide could be obtained"--Abstract, p. i

Effect Of Hydroxyethyl Cellulose On Properties Of Concrete At Early Ages., Vipinchandra R. Shah

Masters Theses

"In this investigation, hydroxyethyl cellulose was used as an admixture in plain concrete. The admixture was tested for its effect on the compressive strength of plain concrete cylinders and for its effect on the flexural strength of plain concrete beams. Specimens were also tested for freeze-thaw durability and shrinkage.

The test results indicated that hydroxyethyl cellulose has the effect of increasing the compressive strength and decreasing the flexural strength of plain concrete. The rapid freezing and thawing tests showed that the durability increases with increase in amount of admixture.

The tests were carried out in the Materials Laboratory of the …

The Effect Of Plastic Deformations On Grain Boundaries., Jayendra Jamnadas Shah

Masters Theses

"The purpose of this study is to determine the effect of the plastic deformations on the grain boundaries and the grain structure of mild steel. Five beams tested were of A-36 steel and of 6 WF 20 rolled section. Central loading was used to develop a plastic tinge at the cent1:1r.

At the center, where a plastic hinge was formed, the effect of the plastic deformations on the grain structure was severe in all the samples taken from the tension side of all plastically or partially plastically loaded beams. In fully plastically loaded beams this effect had spread on both …

Effect Of Internal Pressure On Compressive Buckling Stress Of A Cylindrical Shell Under Eccentric Loading, Chao-Ping Chu

Masters Theses

“In this paper, an investigation was made of a thin- walled cylindrical shell under compressive load with various eccentricities and internal pressures to study the effect of the internal pressure on the compressive buckling stress of the shell.

So far, theoretical methods have not been devised to solve this problem; therefore, an experimental study was carried out. The experimental results indicated that the buckling load of the shell decreases as the eccentricity increases, that the buckling stress increases as the eccentricity increases, and that the change in buckling stress increases with an increase of internal pressure and is very nearly …

Nature And Lateral Variation Of Lost Rock Limestone In The Tri-State Zinc-Lead District., Adnan A. Saadallah

Masters Theses

"The nature and lateral variation of a host rock limestone in the Tri-State zinc-lead district were petrographically studied within a single horizon, the M bed. This bed is a massive crinoidal limestone in the Tri- State district of southwestern Missouri, northeastern Oklahoma and southeastern Kansas and is a part of the Mississippian Keokuk Formation.

One hundred and twenty specimens from this bed were collected underground from six pull drifts in five mines: West Side, Grace B, Big John, Little Greenback, and Mudd Mines. The specimens were collected at regular intervals, usually ten to twenty feet, beginning at the edge of …

A Study Of Methods For Estimating Parameters In The Model Y(T) = A₁E-P₁T + A₂E-P₂T + Ε, Gerald Nicholas Haas

Masters Theses

“In this study, methods for estimating the unknown parameters A₁, A₂, p₁, and p₂ in the model
y(t) = A₁e^-p₁t + A₂e^-p₁t + ϵ
where ϵ ~ N(0, σ) are investigated. In the model investigated, A₁, A₂, p₁, and p₂ are positive.

Four methods, one non-iterative method and three iterative methods, for estimating parameters in this model are investigated. The non-iterative method is known as Prony's Method. The three iterative methods are (1) the Modified Gauss …

A Theoretical And Experimental Study Of The Stress Distribution In An Infinite Plane Shrink-Fitted On Four Circular Elastic Pins, Charles H. White

Masters Theses

"The purpose of this study is to show a general method of solution for multiple inclusions in an infinite plane. The shrink-fitting of an infinite plane upon the inclusions, or pins, will be simulated by force-fitting the pins into a large sheet of birefringent material, to obtain an experimental verification of the analytical solution.

The problem to be approached is that of four circular elastic pins shrink-fitted in an infinite plane. The method of superposition will be used, and the stresses at any point in the plane found with respect to a common origin of coordinates. It will first be …

Structural Analysis Of Open Channels On Elastic Foundation., Wan-Cheng Liu

Masters Theses

"This study is to analyze continuous open channels used for fluid flow and supported on soil which is considered to provide an elastic foundation. The basic assumption is that the reaction forces of the foundation are proportional at every point to the deflection of the channel at that point. The walls of the channel are considered vertical in all cases but are subjected to various lateral pressures due to different embankment loading conditions"-- Abstract, p. ii

The Effects Of Granular Size On The Thermal Conductivity Of Fine Sand, Fikri Yalvac

Masters Theses

"The Thomas method (1) for determining the thermal conductivity of solid materials can be used for the determination of the thermal conductivity of granular materials. In this thesis this method has been used to determine the effect of the granular size of sand cn its thermal conductivity.

River sand was classified according to size by the Tyler Standard Screen Scale into 50-60, 50-80, 80-100, 100-200, and below 200 mesh size. These sands were used for the experiments. The clay was separated from these samples to obtain pure river sand for the experiments.

According to the International Critical Tables, the thermal …

Study Of The Temperature Dependence Of The Haeffner Effect In Mercury, Charles George Arnold

Masters Theses

“In 1953, E. Haeffner (1) reported that after he had passed a direct electric current through a capillary tube filled with mercury, he obtained a separation of the isotopes of mercury. It was found that the heavier isotopes were enriched at the negative terminal and the lighter Isotopes at the positive terminal. This effect has since been referred to as the Haeffner Effect. Since this original experiment, other investigators have observed this effect in many other liquid and some solid metal systems.

The work of J. N. Baysden (2) showed that the separation of the isotopes in mercury could be …

Correlation Between Drying Times Of A Vinyl Copolymer Solution And Properties Of Dried Films., Abd El-Rahman M. Naser

Masters Theses

"One of the common methods used in film formation is the solvent evaporation method. As the evaporation starts the viscosity increases due to the inability of the solvent to keep the chains apart, which leads to a drag between molecules.

The rate of evaporation of the solvent (loss of solvent) cannot be equated with the rate of drying, since the latter depends on the results of the loss of solvents in terms of viscosity and plastic properties. The drying time can be defined as the rate at which a film increases its viscosity and thus changes the properties of a …

A Rubber Membrane Analogy For The Study Of Shafts In Torsion., Myron D. Bruns

Masters Theses

"The thesis presents a review of literature giving reference to several books which present the many and varied methods of determining the shearing stresses in shafts. However, no reference was found that used a rubber membrane analogy similar to that used in th is thesis. The theory of torsion, the membrane theory, and its analogy have been presented for a better understanding of the subject. Illustrations are used freely for clarity.

Analytical methods and solutions are given for two problems. The first method is that of writing a Saint-Venant stress function and satisfying the necessary conditions for it to be …

Use Of Sr-4 Strain Gages Under Hydraulic Pressure, Manubhai M. Patel

Masters Theses

"In this investigation an attempt has been made to determine the effects of hydraulic pressure on SR-4, type A-5 strain gages. A thick-walled aluminum alloy cylinder without end constraint was used to make an experimental study of the effects of hydraulic pressure on these strain gages.

The behavior of this cylinder under different internal hydraulic pressures was also studied by measuring the strains by means of strain gages which were attached to the inside and outside surface of the cylinder. The problem has been studied by applying pressures up to 4800 psi.

Because of the high internal fluid pressures various …

The Design, Construction, And Operation Of A Conducting Field Analog Computer., Richard T. Johnson

Masters Theses

"The purpose of this investigation is to design and construct a simple conducting field analog to solve problems described by the two-dimensional Poisson or Laplace equations. Decisions concerning choice of conducting media, construction of problem models, and design and construction of a specialized power supply with instrumentation were based on the results of previous experiments. Several problems are solved using the designed apparatus. Partial solutions to these problems are displayed in graphical form.

The greatest deviation of the experimental results from iterative values was consistently less than 8%. In most cases the deviation was less than 6%. The console arrangement …

Stability Investigation Of Pipe-Line Suspension Bridges, Ten-Hsi Chen

Masters Theses

“This thesis presents an analysis of the behavior of pipe line suspension bridges under the action of wind. From this analysis a differential equation of vertical vibration is derived and solved, and the possible methods of preventing its vibration are discussed and suggested”--Abstract, page ii.

Minimum Frictional Characteristics Of Optimum Journal Bearings., Navinchandra F. Shah

Masters Theses

"This investigation was conducted to develop a graphical representation to determine the optimum bearing conditions for minimum friction and to establish a theoretical approach for journal bearing design.

A series of graphs has been plotted for· the coefficient of friction versus the eccentricity ratio based on the. Sommerfeld number derived from Reynolds' differential equation, f or optimum journal bearings.

The results obtained in this research have been compared with those developed by other investigators. This comparison confirms the validity of the results presented in this thesis, so that it could be used advantageously for the design of optimum journal bearings"-- …

Solubility And Structure Studies Of Nickel (Ii) Acetate, Richard J. Baird

Masters Theses

"The effects of ammonium acetate on the solubility of anhydrous nickel (II) acetate in anhydrous acetic acid was investigated and was found to behave similar to the zinc (II), copper (II), and cobalt (II) systems. Problems with equilibrium, encountered by previous investigators, were overcome. The determination of the structure of nickel (II) acetate hemiacetate was atacked by infrared studies, preparation of adducts, cryoscopic studies, magnetic susceptibility measurements, and absorption spectra. It was found that nickel (II) acetate hemiacetate is octahedrally coordinated with two coordination sites vacant. It was shown that the binuclear cage structure common to copper (II), chromium (II), …