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A Method Of Predicting The Economic Effects Of Highways In Undeveloped Countries., Mohamed Magzoub Abdallah

Masters Theses

"This paper reviews the findings of the socio-economic impact studies pertaining to land-use changes. An attempt is made to explain, through land-use studies, the relationship between the past and future development of the City of Rolla, Missouri, and the system of highways serving the city, The relationship between land-use changes, expressed in active units rather than areas, and the level of activity related to those changes, rep resented by 0-D traffic volumes, is studied for Rolla and the difference in the behavior of this relationship in undeveloped countries is discussed"-- Abstract, p. ii

A Geochemical And Microscopic Study Of A Recently Discovered Deposit In Southern Illinois Fluorspar District., Prachon Chareonsri

Masters Theses

"A bedding-replacement fluorite deposit, discovered by recent drilling in the northeast part of the Cave in Rock district, southern Illinois, has been studied by a combination of geochemical, X-ray, and microscopic techniques. The dispersion pattern for trace zinc, lead, cadmium and copper concentrations in carbonate host rocks adjacent to the fluorspar deposit, determined by atomic absorption spectrophotometry, appears to hold only little hope in serving as an aid to exploration. Only cadmium anomalies appear closely related to the known fluorspar ore, and those values are not greatly above background.

Broad zinc and cadmium anomalies and a narrow lead anomaly are …

A Comparison Between Direct Waves And Head Waves In A Seismic Refraction Profile., Nelson Jose Aboud Garcia

Masters Theses

"The purpose of this investigation was to experimentally verify the theoretical prediction that the particle velocity of a head wave is the time integral of the particle velocity of a direct wave.

The procedure was to use small explosions in the field to generate direct waves and head waves in a surface layer of low compressional velocity overlying a higher velocity medium. The direct waves were distinguished by the ratio of frequencies and by the slopes in a time distance plot.

The result of comparing the particle velocity of the head waves with the integral of the particle velocity of …

An Optimization Method For Scheduling Nuclear Reactor's Refueling St. Louis County, Missouri., Abbas Razavi

Masters Theses

"This paper describes a method to optimize the refueling schedule of the nuclear units. The method finds a mid-range (five to ten years) optimum refueling schedule by varying the refueling date of the nuclear units. The cycles of the nuclear units are the variable parameters, with fuel enrichment and quantity being fixed.

An empirical technique is used to calculate the nuclear fuel cost. Seasonal constraints are taken into account, and no nuclear unit will be shut down while another is down"-- Abstract, p. ii

An Examination Of The Adaptive Random Search Technique., Mark William Heuckroth

Masters Theses

"Random search procedures have recently been successfully applied to the optimization o f a variety of chemical engineering problems, including optimization of chemical processes by flow sheet simulation. These procedures represent the independent variables as random variables described by probability distributions. The adaptive random search procedure centers the distribution for each variable about the best search point found and examines this region for a better point. Thus, this technique has the ability of continuously moving the search region toward the optimum, which is particularly advantageous in following constraints.

This study examines the efficiency of the adaptive random search technique as …

Analysis Of The Stresses Induced In Rock By Rock Splitters., Diogenes De Jesus Chollett

Masters Theses

"The method of solution of the problem of determining the stress and displacement distributions around an unfractured circular hole subjected to nonuniform applied internal pressure located in an infinite plate is developed. Two problems are solved for two different representative boundary conditions. The problem of determining the stress distribution around a circular hole with two symmetric radial cracks subjected to nonuniform applied radial pressure located in an infinite plate is analyzed and developed for further solution"-- Abstract, p. ii

An Investigation Into The Extent Of Implementation Of Operations Research Techniques For Inventory Control In Industry., Edward Allen Scarff

Masters Theses

"The object of this research is to investigate the techniques currently utilized for controlling inventories in industry. The various significant methods of inventory control in use today are presented and the strengths and weaknesses of these methods are assessed.

A survey of the Fortune 500 companies was conducted to determine the methods of inventory control in use today by industry. In addition, selected production personnel of representative companies were interviewed to determine the advantages and disadvantages of certain inventory control methods they use.

The results of the survey and the interviews are presented, and an analysis is made. Conclusions are …

A Study Of Several Substitution Ciphers Using Mathematical Models., Wanda Louise Garner

Masters Theses

"This paper will consider vector and matrix representations for several polyalphabetical substitution ciphers. Classical ciphers such as the Vigenère, the True Beaufort, the Variant Beaufort, and the autokey will be included. We shall also discuss ways to mathematically vary a substitution cipher. In addition, we shall employ our mathematical representations to decipher a fixed matrix substitution cipher"--Abstract, p. ii

The Development Of A Selection Model For Coal Conversion Processes., Karen Aldridge Dollar

Masters Theses

"Present research endeavors involving coal conversion technology have encompassed comparisons of the processes on the basis of economics or efficiency. These comparisons lack completeness because many intangible factors pertinent to the evaluations of the processes have been ignored.

A model has been developed to aid in the selection of the optimum coal conversion process for a given situation. The model includes a method for the evaluation of quantifiable factors which affect the decision-making procedure, and also includes methods by which the non-quantifiable factors which are important to the situation may be evaluated. This is a more complete form of decision-making …

Measurement Of Growth Rate To Determine Condensation Coefficients For Water Drops Grown On Natural Cloud Nuclei., A. M. Sinnarwalla, Darryl J. Alofs, J. C. Carstens

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Growth Rate Measurements Were Made for Water Drops Grown on Nuclei in Atmospheric Air Samples Taken in Rolla, Missouri. Rolla, Having a Population of 15,000 and Very Little Industry, is Relatively Free of Urban Pollutants. the Measurements Were Made in a Vertical Flow Thermal Diffusion Chamber at Supersaturations of 0. 5 and 1%. the Time to Grow from Near Dry Radius to the Final Radius (6 to 7. 5 Mu M) Was Measured. If One Assumes the Thermal Accomodation Coefficient is Unity, the Measurements Indicate an Average Value of 0. 026 for the Condensation Coefficient. the Temperature Ranged from 22. …

Multimedia Dispersion Relation For Surface Electromagnetic Waves, C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

We Have Derived a General, N-Media Dispersion Relation for Surface Electromagnetic Waves Propagating on Isotropic Layers with Complex Dielectric Functions. the Equation is Presented in a Convenient, Compact Form for Ease of Application. Copyright © 1975 American Institute of Physics.

Strain Effects On The Esr Spectrum From Antimony Donors In Germanium, Edward Boyd Hale, John R. Dennis, Shih Hua Pan

Physics Faculty Research & Creative Works

The electron-spin-resonance spectra from surface-strained (but not externally stressed) antimony-doped germanium are investigated in detail. Experimental data are given for the linewidth, line asymmetry, and line-shape reversal feature as well as for the changes in donor concentration, temperature, and surface conditions. The donors of interest occur in a surface layer several microns thick. A theoretical analysis is based on the Kohn-Luttinger formulation for a shallow donor electron, which is forced by surface strain to predominately occupy a [111] conduction-band valley minimum. A substantial distribution in strain among the donor sites is necessary to account for the line-structure features. These features …

Electron Impact Autoionization In Heavy Alkali Metals, Kaare J. Nygaard

Physics Faculty Research & Creative Works

Autoionizing levels in cesium, rubidium, and potassium have been studied by electron impact in a crossed-beam apparatus. Comparisons are made with the binary-encounter calculations of Roy and Rai. The effects of autoionization and inner-shell ionization have been overestimated in the theory. © 1975 The American Physical Society.

Determination Of Oxygen Chemical Diffusion Coefficients In Single Crystal Srtio By Capacitance Manometry, D. B. Schwarz, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The oxidation kinetics of a single crystal of SrTiOs were measured with a tensivolumetric system over the temperature range 700 -975 at 0.03 atm oxygen pressure. The oxidation was found to be oxygen diffusion limited with an activation energy of 14.9 - 1.3 kcal/mole. Combining the kinetic data with relative defect concentration data yielded an activation energy for oxygen self-diffusion of 57 - 16 kcal/mole. The enthalpy of formation of doubly ionized oxygen vacancies was calculated to be 126 - 13 kcal/mol. © 1975, The Electrochemical Society, Inc. All rights reserved.

Mechanism Of Uai3 To Uai4 Transformation, Ling Ping Lee, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

The compound, UA14, which forms during the peritectic reaction (Liquid + UA13 → UAI4), has a long needlelike shape and reveals the characteristic morphology of a fishtail when cut along the long axis. When cut perpendicular to the long axis, it shows an internal core of another phase, which has been identified as a primary aluminum solid solution. Because of the interesting relationship between the crystallographic structures of UA13 and UA14, the peculiar UA14 morphology can be explained on the basis of a proposed mechanism. The mechanism of UA13 to UA14 transformation has been identified as shear and diffusion controlled …

Centralized Solar Wind Home Heating, Russell Peterson, Duane Cromack

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

In the immediacy of national goals for energy independence, the need emerges to use dialectic methods to diminish the energy consumptive characteristics of the typical home.

At the cutting edge of resourceful progress are the residential developments which embrace alternative and conservative energy techniques. In conjunction with such a planned, low impact community, this paper proposes a cluster-centralized system which utilizes wind energy in combination with solar thermal energy for space and domestic water heating.

A description of the random solar-wind resource embodies a matching problem that in turn reveals the benefits of the combined mode of energy collection. Though …

Direct Ac Generation From Solar Cell Arrays, Fernando L. Alvarado, Adel H. Eltimsahy

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Results of the investigation of the performance of solar cells when directly coupled to a conventional three-phase power network are presented. This approach dissociates the electricity production problem from the electric energy storage problem. Extensive studies of the required power inverter are performed. Preliminary simulation results indicate that ac power outputs of better than 90% of the optimum cell power output can be easily achieved by means of a suitably controlled inverter, thereby justifying the elimination of dc loads or local dc electric energy storage devices. It is also shown that the controlling policy for the inverter must depend on …

Biquadratic Exchange And First-Order Ferromagnetic Phase Transitions, Harry A. Brown

Physics Faculty Research & Creative Works

We have calculated some properties of a ferromagnet using a Heisenberg Hamiltonian with a biquadratic exchange term added. The constant-coupling approximation was employed. If the strength of the biquadratic exchange relative to the bilinear is given by a dimensionless parameter α, there is a critical value αc at which the phase transition changes character from second order for αα>αc. The spontaneous magnetization, the exchange energy, and the spin-correlation function show discontinuous jumps at α=αc and unstable behavior for α>αc. © 1975 The American Physical Society.

Analogy Between Spinodal Decomposition And Martensitic Transformation, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

The translation of the theory developed for the spinodal decomposition of a supercooled alloy to the language appropriate for the martensitic transformation is carried out. In the spinodal theory, the stability of the alloy with respect to the composition fluctuation is examined, while in the present theory the stability of the crystal with respect to the shear displacement fluctuation, the transverse phonon, is studied. The analogy to the spinodal theory requires the revival of the strain gradient energy term or the couple stress term, the presence of which has been a subject of controversies for a long time since Laval. …

A High-Power Pulsed Xenon Ion Laser As A Pump Source For A Tunable Dye Laser, Laird D. Schearer

Physics Faculty Research & Creative Works

An inexpensive pulsed xenon ion laser with peak power outputs up to 4 kW has been constructed and used as a pump source for a tunable rhodamine 6G dye laser with a 0.25-A bandpass in the yellow-red range of the spectrum. The dye laser is tunable from 5465 to 6300 A. Over 50 W are obtained at the peak of the tuning range. Copyright © 1975 by The Institute of Electrical and Electronics Engineers, Inc.

Excitation Of Atomic Hydrogen To The N=2 States By 15-200-Kev Protons, John T. Park, J. E. Aldag, J. M. George

Physics Faculty Research & Creative Works

Cross sections for the process H+ + H H+ + H* (n=2) are determined from the energy-loss spectra of 15-200-keV protons. After normalization at 200 keV to the Born approximation, the maximum value (1.07 x 10-16 cm2 at 60 keV) lies below close-coupling calculations and above Glauber-approximation calculations. The agreement with low-energy (5-30-keV) data of others is very good. © 1975 The American Physical Society.

Use Of The Psi Technique In Prerequisite Courses, John T. Park, William R. Snow

Physics Faculty Research & Creative Works

An engineering physics course, in which the Personalized System of Instruction (PSI) technique has been used, has been designed to meet the requirements that all of a prescribed list of subjects be covered and that the course be completed within a single semester. The course was modified so that it has two levels of mastery for each unit: a passing level and a complete mastery level. All students were required to reach a passing level of mastery on all of the required material. Grades were assigned according to the number of complete mastery level examinations passed. It was found that …

Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin

Physics Faculty Research & Creative Works

The relative photoionization cross sections for cesium atoms selectively excited to the 6P32,122 states have been measured in a triple-crossed-beam experiment. A cesium discharge lamp produced resonant wavelengths of 8521 and 8944 for the excitation process. A Hg-Xe lamp combined with a grating monochromator was used for the actual ionization in the wavelength region from 2500 to 5000. Background counts due to photoionization of ground-state cesium atoms and dimers as well as various surface effects were discriminated against by chopping the excitation light source. The data are compared with results from radiative-recombination measurements in which the fine-structure levels are not …

Erratum: Multimedia Dispersion Relation For Surface Electromagnetic Waves. (The Journal Of Chemical Physics (1975) 62 (1674)), C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

No abstract provided.

Surface Electromagnetic Waves On Layered Systems With Damping, C. A. Ward, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

The Dispersion Curves, Propagation Distances, and Poynting Vectors of Surface Electromagnetic Waves Propagating on a System of Cu-Cu2O-Air with Variable Film Thickness Have Been Calculated using the Full Dispersion Realation Including Damping. Double-Dip Structure in the Propagation Distance for Intermediately Thick overlayers, the Shifting of One Dip Below ΣTO, and the Presence of the Other Dip at ΣLO Are Explained in Terms of Features of the Dispersion Curve. the Complete Poynting-Vector Calculations Show that Predictions of Field Bunching at ΣLO Are Probably in Error. © 1975 the American Physical Society.

The Use Of Surface Electromagnetic Waves To Measure Materials Properties, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

An Elementary Introduction to Surface Electromagnetic Waves (SEW) is Presented. the Emphasis is on Those Features of SEW Which Make Them Useful for Measuring Optical Properties of Thin Layers on Metals. the So-Called Two-Prism Technique for Making Such Measurements is Discussed, Some Preliminary Experimental Results Are Given, and Some Possible Applications Are Presented. © 1975.

Double Reflection Dips From Grating Ruled Semiconductors, L. F. Teng, Ralph William Alexander, Robert John Bell, B. Fischer

Physics Faculty Research & Creative Works

The Double Reflectivity Dips, Previously Observed by Fischer Et Al. and Anderson Et Al., Which Appeared in the Reflection Spectra of Grating Surfaces On, the Te‐doped Semiconductors GaAs and InSb Around Both the Plasmon and Phonon Frequencies Have Been Measured in More Detail. in the Plasmon Region, Several Possible Explanations of the Phenomenon Are Discussed, But the Favored Explanation Involves Surface Damage. a Simple Two‐region Reflectivity Equation Checked with a Rigorous Grating Theory is Proposed and is Shown to Fit the Data Well. Copyright © 1975 WILEY‐VCH Verlag GmbH & Co. KGaA

Transport Phenomena In Thermally Stratified Boundary Layers, D. W. Pepper, S. C. Lee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Studies of heat, mass, and momentum transfer are made to analyze the formation of marine fogs in thermally stratified boundary layers in the atmosphere. The governing partial differential equations of continuity, momentum, temperature, and concentration are used to describe the transport phenomena. An additional equation of turbulence energy is introduced to account for the development of the turbulent motions. Simultaneous solution of this system of equations allows the turbulent exchange coefficients to be treated in the same way as all other dependent parameters. Verification of the theoretical approach is made by comparing the numerical predictions with wind tunnel simulations of …

Locating The St. Louis Urban Plume At 80 And 120 Km And Some Of Its Characteristics, J. F. Stampfer, J. A. Anderson

Chemistry Faculty Research & Creative Works

The feasibility of locating the urban plume of a moderately large urban area, as far as 120 km downwind, is shown. The method utilizes a single engine aircraft and aerosol instrumentation. A summary of the data obtained from 34 flights, during an 8-month period, is presented and the problems involved in interpreting the data are discussed. These difficulties include nonuniform background levels outside the plume, changing relative humidity, low wind speeds and stable atmospheric layers. The plume was characterized by concentrations of small particles (0.15 < r < 0.3 μm) ca. 1.5 times that in background air and concentrations of large particles (0.3 < r < 1.3 μm) usually greater than twice that in the background. The ratio of the concentrations of small particles to large particles in the plume was about one-half of that in the background. © 1975.

Bit Penetration Into Rock - A Finite Element Study, Jaw-Kuang Wang

Doctoral Dissertations

"A finite element approach has been developed to simulate bit penetration from bit-rock interaction to chip formation. A mathematical rock failure model, based on a review of the existing literature on rock tests, has been proposed to represent post-failure rock behavior and applied in the penetration simulations. The finite element program has been developed for two dimensional plane strain problems with non-linear material properties, geometrical nonlinearities and fracture. An anisotropic element as well as variable stiffness and stress release methods have been used. An iteration method, using an incremental approach, has been applied for continuous penetration and modifications of material …