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An Analysis Of The Simulated Inductande Obtained From Forward Biased Semiconductor Diodes., Everett Harold Vannoy

Masters Theses

"The problem undertaken in this thesis is to study the simulated inductance observed in forward-biased abrupt junction p-n diodes with a highly doped p region and a nearly intrinsic n region and show that it is due to conductivity modulation. Unlike other analyses of this phenomenon, a voltage step is applied to the diode in such a direction as to forward bias it and the behavior of the injected minority carriers are observed. By comparing the resultant current through the diode to the relationship predicted by the equivalent circuit of the diode, an expression is obtained for the simulated inductance. …

Forced Convection Heat Transfer Coefficients And Induction Heating, Max Edwin Light

Masters Theses

“The purpose of this study was to design and build an apparatus to experimentally determine the convective heat transfer coefficients for water flowing in a horizontal tube at turbulent flow. Also it was planned to use the apparatus to investigate the spatial dependence of energy deposition by induction heating.

An instrument and measuring techniques were developed that gave reasonable correlations between experimentally determined heat transfer coefficients and values calculated from generally accepted heat transfer relationships developed by other experimenters. Most of the calculated values were within ± 10% of the experimental values for a wide range of flow rates.

It …

The Effects Of Granular Size On The Thermal Conductivity Of Sand, Kanubhai M. Patel

Masters Theses

"The thermal conductivity of granular materials can be determined by the Thomas method. This method was used here to determine the effects of granular size on the thermal conductivity of sand. A river sand was secured and screened. The sand retained between the Tyler Standard Screen Scale, mesh 10 and 14, 14 and 28, 28 and 40, 40 and 48, 48 and 60, and below mesh 60, was used for tests.

The thermal conductivity for the above six samples obtained by the author coincide fairly well with published data.

It is reported in the International Critical Tables that the thermal …

The Resolution Of Two Known Signals In White Gaussian Noise., Peter Cheng-Fang Wang

Masters Theses

"The problem of resolving two signals F1(t) and F2(t) in white Gaussian noise n(t) is treated here as a problem in statistical decision theory. We assume a situation in which one of two similar signals is present and an observer is asked to make a decision concerning which of the signals is present with a tolerable probability of error. The observer is allowed to use the best system which he can design for this particular purpose. Of course, this observation will be disturbed by noise and therefore, the observer is led to ambiguous selections. It is apparent that the optimum …

Optimum Zero-Memory Nonlinear Filter, Benjamin Shaw-Hu Wang

Masters Theses

“The purpose of this report is to review the basic work described by Zadeh insofar as systems of class N₁ are concerned and to apply his general results to a specific problem in which a non-linear filter is mandatory simply because the linear filter is essentially ineffective. The ineffectiveness stems from the fact that the autocorrelation function of the signal plus the noise has essentially the same variational character as the signal alone. Therefore, the transfer function of the linear filter turns out to be simply a constant. Thus, the output of the linear filter is just an attenuated …

Sonic Flow Meter., Daniel E. Wilson

Masters Theses

"The purpose of this thesis was to construct a device to measure the velocity of air employing sound waves. The principle of operation of the device is that the time interval required for the sound wave to travel between two points in the duct is a function of the fluid velocity. This time interval was measured both with the air flowing and with the air stationary. An equation was derived such that the mean velocity of the flowing air could be calculated by knowing the two-time intervals.

The mean velocity determined by this device was compared to the mean velocity …

Radiation Characteristics Of A U-Slot Antenna., Richard Paul Brueggemann

Masters Theses

"The radiation equations for a simple rectangular slot antenna are derived as a function of the field distribution in the slot. The electric field distribution in the slot is then formulated as a function of the aperture dimensions. The U-shaped slot antenna is described as an extension of the rectangular slot theory and the actual field is measured in the slot for comparison.

The far field equations a.re derived for the U-slot antenna similar to those for the rectangular slot antenna and are evaluated using the formulated distributions in the slot for antennas of two different electrical sizes. The equations …

Generalized Programs For Heat Transfer Analysis., Ceylung Chu

Masters Theses

"This report presents numerical methods for calculating temperature distributions in any physical system in which heat transfer is taking place. The syste.11 may be at either a steadystate condition or a transient condition. The temperature distribution may itself be or primary interest, or it may be used further to calculate the flow or heat or thermal stress.

The system under investigation is divided into a certain number of subdivisions, or so-called "regions". A reference point (node point) will be taken as representative for the region which includes that point. The temperature at the "node point11 is taken to be the …

The Characteristics Of Radial Strain Propagation Induced By Explosive Impact In Jefferson City Dolomite., Choon K. Quan

Masters Theses

"Blasting effects depend largely on peak radial strains propagated in rock media by explosive impact. To improve blasting design and control of secondary effects (e.g., structural fatigue), an equation for peak radial strain propagation induced by explosions was developed as follows: Emax = K e^-αr /r

An instrumental technique was designed to test the validity of the equation in the Jefferson City dolomite. Results showed ii that for 1-lb charges of 60% ammonia-gelatin explosive, peak strains, at any distance r, were reduced in amplitude in accordance with an exponential decay function of the type Emax = 281 e^{-0.026r …}

Studies Of An Electrical Method For Generating Ultrasonic Waves, Yung-Yien Huang

Masters Theses

“Ultrasonic waves have proved very valuable in the observation of both the velocity and the absorption coefficient of sound in various media. From the velocity measurements of ultrasonic waves in metals, it is possible to obtain elastic constants, such as the compressibility, and the specific heat. Also, the observed attenuation depends greatly on the type and structure of the material. One of the widely used methods for investigation of the internal losses in solid state physics is the pulse-echo technique. This method is being used almost exclusively in internal friction investigation"--Introduction, page 1.

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 …

Estimation And Tabulation Of Bias Coefficients For Regression Analysis In Incompletely Specified Linear Models., Harry Kerry Edwards

Masters Theses

"There is often some uncertainty as to the exact number of predictors to include in the specification of the linear model when the theory of regression analysis is applied to specific data. To aid the experimenter in defining the correct number of predictors, a bias function that estimates the deviation of a linear model from the true model has been defined.

The writer has derived an accurate, economical, numerical method for calculating the bias function associated with an incompletely specified linear model and has tabulated bias function coefficients for a reasonable number of doubtful predictors"--Abstract, page ii.

A Parameter Perturbation Procedure For Obtaining A Solution To Systems Of Nonlinear Equations., James Carlton Helm

Masters Theses

"For simultaneous nonlinear equations the convergence of the known functional iterative procedures is dependent upon a good initial approximation to the desired roots. In this paper the restriction on the choice of the initial approximation has been circumvented by dividing each problem into a number of subsidiary problems in accordance with a parameter perturbation procedure. The study presents a discussion of the algorithm and the conditions for convergence. The discussion, also, includes the problems which were solved using the parameter perturbation procedure"--Abstract, p. ii

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 …

Experimental Evaluation Of Thermal Stresses On The Outer Surface Of A Thick-Walled Tube., Vinodray T. Patel

Masters Theses

"In this investigation an attempt has been made to measure thermal stresses on the outer surface of a thick- walled tube. The inside surface was heated by steam passing through the tube while the outer surface was cooled by water. Two temperature compensated strain gages were used to measure strains in the tangential and axial directions respectively. The advantage of using this type of strain gage is to avoid the use of a dummy gage to compensate for the temperature effect.

The analytical solution to the problem was derived and the values of thermal stresses were calculated theoretically and compared …

Longitudinal Spin Relaxation Of Optically Excited Rubidium., John Robert Martin

Masters Theses

"This thesis is intended to be a guide to the theory and experimental procedures of optical pumping in one of its most usual applications. It is also intended to be an extension of the work done here by Steinbruegge¹ in 1963 along with several significant changes and improvements in experimental techniques. A study is made of the optical pumping of rubidium vapor, and results are given stating the most efficient methods with which to produce large populations of optically oriented rubidium atoms, and thereby determine the relaxation properties of a given rubidium system"-- Abstract, p. ii

Study Of Mass Transfer In Oscillating Droplets., Subhash Vishnu Gangal

Masters Theses

"The object of this investigation was to study the resistance to mass transfer inside single oscillating liquid droplets falling in a liquid medium. The following four systems were studied: (1) 3% acetic acid in nitrobenzene and water, (2) 25% acetic acid in nitrobenzene and water, (3) 3% acetic acid in nitrobenzene and glycerin in water, and (4) benzyl alcohol and water. The individual mass transfer coefficients were computed by using the Handlos and Baron relation and were compared with the experimentally determined dispersed phase mass transfer coefficients. The average absolute deviation of the observed values of dispersed phase mass transferred …

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 …

Transverse Spin Relaxation Of Optically Pumped Rubidium., Robert Evans Hufft

Masters Theses

The study of the transverse spin relaxation of rubidium vapor is a continuation of the work done by Kenneth Steinbruegge¹ and that in progress by John Martin² at the University of Missouri at Rolla. The purpose of the experiment is to study the change of intensity of the transmitted pumping light at resonance in the longitudinal direction, and the observation of the high frequency modulation of a second "cross" beam of light perpendicular to the first. Under resonant conditions this "cross" beam will exhibit a phase coherence and a loss of phase coherence when parameters of the experiment …

Influence Of Quartz Particle Size And Concentration On The Fracture Stresses Of Triaxial Alumina Porcelain., John David Weyand

Masters Theses

"Quartz particles were introduced into a typical triaxial alumina porcelain. Three levels of particle size and three levels of concentration were studied. The strength sample sizes were large. A diametral- compression loading method was used for strength testing. It was found that the porcelain strength decreased with increasing grain size and concentration of quartz particles. A linear relationship existed between log quartz concentration and mean fracture stress"--Abstract, p. ii

The Dielectric Properties Of Thallium Nitrate., Gene E. Gowins

Masters Theses

"The purpose of this research was to investigate the dielectric behavior of thallous nitrate and to determine whether it belongs to space group Pbnm or to Pbn2.

The growing of single crystals of thallous nitrate which are suitable for dielectric measurements is difficult because the crystals are prone to initiate a dendritic growth habit. In the present work single crystals of thallous nitrate were obtained, however, by slow evaporation of an aqueous solution at 55 degrees centigrade. The crystals were plates, not larger than 8 x 8 x 2 mm, whose principal faces were subsequently indentifled as (001) planes. The …

A Study Of Stability Of Numerical Solution For Parabolic Partial Differential Equations., Tsang-Chi Huang

Masters Theses

"Parabolic partial differential equations hold a very important position in science and technology since they are encountered frequently in the solution of diffusion and heat-conduction problems. Theoretically, it is possible to solve many of these equations by analytical methods, but the modern development of mathematics has revealed that there are numerous difficulties in obtaining the solution. Numerical solutions for most applied problems of a parabolic partial differential equation type are practically necessary, thus methods for numerical solution or approximate solution became more important. Since numerical results are required for most applied problems of a parabolic partial differential equation type a …

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 …

A Study Of Plane And Spherical Compressional Waves In A Voigt Viscoelastic Medium, Gerald B. Rupert

Doctoral Dissertations

"In investigating the behavior of waves traveling through cohesive solids, two assumptions are usually made: that the propagating medium is either elastic or viscoelastic, and that the wave is either planar or spherical in form. For small distances from the source of the disturbance the medium can be considered elastic and the wave spherical rather than planar. The assumption of elasticity allows considerable simplification of the mathematical analysis, and assuming a spherical wave form is an acceptable approximation if the initial disturbance is essentially a point source and the propagating medium is nearly homogeneous. However, for large distances from the …

A New Determination Of The Homogeneous Nucleation Rate Of Water In Helium, Edward Francis Allard

Doctoral Dissertations

"The object of this investigation is to apply the best known cloud chamber techniques to the study of condensation phenomena, directed mainly toward the development of a precise method for the determination of homogeneous nucleation rates. A secondary object is to investigate the properties of re-evaporation nuclei so that adequate precautions may be taken to eliminate their detrimental effect in the homogeneous nucleation experiments"--Statement of Problem, page 10.

Petrology And Mineralogy Of Certain Portions Of The Fredericktown Deposits, Farouk El Baz

Doctoral Dissertations

"The Fredericktown area is part of the 'Lead Belt' district of southeastern Missouri, the major lead-producing region in the world for fifty years. The district is a typical example of the Mississippi Valley Type deposits. The ores occur in Upper Cambrian sediments overlying Precambrian rocks.

The Fe-Cu-Pb-Zn (-Co-Ni) - sulphide deposits of Fredericktown occur over a few square kilometers in sediments overlying two 'granite knobs'. The sedimentary units lap upon and pinch-out against these buried basement hills.

The basal sedimentary unit, the Lamotte Formation, is a time-transgressive, marine, submature orthoquartzite. It contains a Boulder Bed at the base or at …

On The Kirkwood Superposition Approximation, Russell V. Cochran Jr.

Doctoral Dissertations

"When the Kirkwood superposition approximation for the triplet distribution function is used in the Born-Green equation for the pair distribution function of a liquid, the fourth virial coefficient is given incorrectly. In view of this, two suggestions for improving the approximation have been investigated. A suggestion, due to G.H.A. Cole, that better results could be obtained by using a second-order integro-differential equation of the Born-Green type with the superposition approximation used for both the triplet and quadruplet distribution functions has been investigated, and results for a hard-sphere model show that this method gives considerably less reliable results than those obtained …

A Study Of Turbulent Mass Transfer In A Wetted-Wall Column, David William Bunch

Doctoral Dissertations

"The field of mass transfer is one of great interest to the chemical engineer. An understanding of this field is vital in the design of many types of chemical processing equipment, particularly in the areas of distillation, extraction, absorption, adsorption, and reactor analysis and design.

However, much of the knowledge in this area at the present time is in the form of empirical relationships, and the basic theory is still not well delineated. This lack of understanding leads to expensive and over-sized or under-sized equipment.

A particular area within this field which needs additional investigation is the theory of mass …