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Reclaiming Mill Tailings Areas, E. R. Bingham Apr 1969

Reclaiming Mill Tailings Areas, E. R. Bingham

Mining Environmental Conference

No abstract provided.


Fm 30-16, Technical Intelligence, 28 February 1969., Robert Bolin , Depositor Feb 1969

Fm 30-16, Technical Intelligence, 28 February 1969., Robert Bolin , Depositor

United States Department of Defense Military Intelligence

This manual defines technical intelligence and explains the technical intelligence process. It briefly discusses the top level Army technical intelligence production organizations, which at that time were Foreign Science and Technology Center, the Missile Intelligence Directorate of the US Army Missile Command, and the Medical Intelligence Office of the Office of the Surgeon General of the Army.

It explains the technical intelligence activities and planning in US Forces in the field.

Considerable attention is given to explaining the proper procedures for recovery and evacuation of foreign equipment and documents.

The appendices contain an extensive list of references, the categories of …


Nuclear Parameter Study In One, Two, And Three Dimensions, Jan Robert Lojek Jan 1969

Nuclear Parameter Study In One, Two, And Three Dimensions, Jan Robert Lojek

Masters Theses

"A parameter study comparing one-, two-, and three-dimensional reactor design analyses was undertaken. Computer programs (codes) were used extensively for the computations and running times on the IBM 360/50 were observed. The values of primary concern were neutron flux shapes, effective multiplication factors, and fuel depletion. Dresden I nuclear power plant with fuel type 1 represents the model reactor. Cross section calculations were performed using the nuclear codes HRG and TEMPEST II, FEVER, EXTERMINATOR-2, AND FLARE generated the nuclear parameters"--Abstract, page ii.


Thermal-Fatigue Of Type 304 Stainless Steel, Gajinder Bir Singh Arora Jan 1969

Thermal-Fatigue Of Type 304 Stainless Steel, Gajinder Bir Singh Arora

Masters Theses

"Thermal fatigue resistance of unrestrained samples of type 304 stainless steel has been investigated under different test conditions. The following studies are reported: (a) effects of heating and cooling rates on the initiation of cracks, (b) effects of upper and lower cycle temperatures on the initiation of cracks, (c) effect of water quenching and (d) the manner in which cracks initiated and propagated. It is shown that under cyclic conditions involving maximum temperatures up to 1000°C, the thermal fatigue life of the material decreases rapidly with rise in the maximum temperature of the cycle. The increase in the lower cycle …


The Effect Of Small Additions Of Niobium Upon The Corrosion Rates And Electrochemical Potentials Of Iron In Hcl, Hf, And H₂So₄, Richard Lee Jones Jan 1969

The Effect Of Small Additions Of Niobium Upon The Corrosion Rates And Electrochemical Potentials Of Iron In Hcl, Hf, And H₂So₄, Richard Lee Jones

Masters Theses

"The valence of niobium ions going into solution was determined by dissolving the metal in hot HF and measuring the volume of hydrogen evolved. The corrosion rates of Nb, NbHx, Fe and Fe - Nb alloys were determined in various concentrations of NCl, H₂SO₄ and HF. The Fe and Fe - Nb alloy samples were made by using powder metallurgy techniques. It was found that a metal skin was produced on the surface of iron corrosion samples if the carbon content of the surface layer was lower than that of the core of the sample. The lower carbon …


Microwave Propagation Through Isotropic Inhomogeneous Photoconductive Media, Thomas Van Doren Jan 1969

Microwave Propagation Through Isotropic Inhomogeneous Photoconductive Media, Thomas Van Doren

Doctoral Dissertations

"The electromagnetic field equations for microwave propagation through a rectangular waveguide filled with a lossy, isotropic, linear, inhomogeneous material are derived in matrix form and solved numerically by computer. The theoretical effects of photo-induced conductivity and dielectric constant variations on microwave attenuation, phase shift, and voltage standing wave ratio are plotted for typical examples in the X-band frequency range. The theoretical calculations indicate that a two order-of-magnitude change in the conductivity can produce a 25 db change in the attenuation or a 100 degree change in the angle of the reflection coefficient. The theoretical predictions are verified qualitatively by experiments …


Computer-Aided Design Of Lossless Non-Uniform Transmission Lines, Larry Lee Wesner Jan 1969

Computer-Aided Design Of Lossless Non-Uniform Transmission Lines, Larry Lee Wesner

Masters Theses

"A numerical iterative design technique is presented for the synthesis of lossless non-uniform transmission lines. A variational approach is used to minimize an error functional to which the system and boundary equality constraints have been adjoined by Lagrangian multipliers. The resultant network optimization conditions lead to an iterative scheme requiring analysis of the non-uniform line, analysis of an adjoint system and calculation of the error gradient in parameter space. A steepest descent procedure is used to optimize parameter values. Finite difference equations are used to provide an approximation model for implementation on the digital computer. A design example and a …


Experimental Determination Of Dynamic Properties Of Aluminum Including Poisson's Ratio, Terry Lee Holman Jan 1969

Experimental Determination Of Dynamic Properties Of Aluminum Including Poisson's Ratio, Terry Lee Holman

Masters Theses

"Two rods of 7075-T651 aluminum are longitudinally impacted to investigate the material's dynamic properties. The test rod, initially at rest, is instrumented with strain gages to record the strain-time history after the impact rod, accelerated to uniform velocity by an air gun launcher, strikes the test rod. A camera records the strain-time pattern displayed on an oscilloscope. The experiment indicates a consistent rise time of approximately 9 µsec. Simple one-dimensional theory correlates well with the experimental data. Compensation is included for the transverse sensitivity of the gages used. The dynamic values for both the modulus of elasticity and Poisson's ratio …


Some Aspects Of Aerated Open-Channel Flow At Shallow Depths And Low Velocities, D. L. Fread Jan 1969

Some Aspects Of Aerated Open-Channel Flow At Shallow Depths And Low Velocities, D. L. Fread

Masters Theses

"This study is concerned with the effect of entrained air bubbles on the open-channel hydraulics of water flowing at low velocities. The air bubbles are introduced into the flowing water by injecting diffused compressed air along the channel bottom. The variations of the velocity profile and velocity distribution energy coefficient of aerated and nonaerated flow are discussed. Empirical equations have been determined for the air concentration and increased depth of flow or "bulking" of the aerated open-channel flow. The investigation revealed a significant increase in the Manning roughness coefficient and the related Darcy friction factor for aerated flow relative to …


Flow In Aggregate-Binder Mixes, Egons Tons Jan 1969

Flow In Aggregate-Binder Mixes, Egons Tons

JTRP Technical Reports

No abstract provided.


Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal Jan 1969

Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal

Masters Theses

"Thermal fatigue is a form of surface failure produced by repeated thermal stresses and is the main cause of die retirement in the die casting industry. A general review of the fundamental and practical aspects of thermal fatigue as encountered in the dies, based on earlier published work, is given and preliminary experiments in an effort to set up a suitable method of testing to study this phenomenon are then described. In the present technique developed to create the thermal conditions experienced by a die steel in aluminum die casting, a small portion of one face of a cylindrical test-piece …


A Theoretical Analysis Of The Free Vibrations Of A Clamped Circular Plate With Damping, Bhalchandra Krishnaji Vaidya Jan 1969

A Theoretical Analysis Of The Free Vibrations Of A Clamped Circular Plate With Damping, Bhalchandra Krishnaji Vaidya

Masters Theses

"A theoretical analysis of the free vibrations of a clamped circular plate was undertaken. The effects of transverse shear were considered for application to relatively thick plates in which there exist sharp transients and frequencies corresponding to higher modes. The method adopted by R. D. Mindlin was used to develope [sic] the differential equation of motion for the plate. The damping effect due to the resistance of the medium in which the plate vibrates was also considered. This damping was assumed to be due to the generation of pressure waves caused by the displacement of the plate...Since the solution requires …


Finite Difference Solutions To Free Jet And Confined Cavity Flows Past Disks With Preliminary Analyses Of The Results, Roland W. Jeppson Jan 1969

Finite Difference Solutions To Free Jet And Confined Cavity Flows Past Disks With Preliminary Analyses Of The Results, Roland W. Jeppson

Reports

A number of solutions are obtained to ideal axisymmetric flow past cavitating disks for both cases of a free surface jet and flow confined in a constant radius conduit. Finite difference methods are utilized in obtaining the solutions from an inverse formulation which considers the velocity potential, and Stokes’ stream function, as the independent variables and the radial and axial dimensions, r and z, as the dependent variables. The resulting inverse boundary value problem for r, for which the basis solution is obtained, is nonlinear. The solution technique uses a Newton-Raphson iteration to evaluate the implicit finite difference operator at …


Electronic Analog Computer Simulation Of The Paez-Pedraza Region Of Venezuela, J. Paul Riley, V. V. Dhruva Narayana, Kousoum S. Sakhan Jan 1969

Electronic Analog Computer Simulation Of The Paez-Pedraza Region Of Venezuela, J. Paul Riley, V. V. Dhruva Narayana, Kousoum S. Sakhan

Reports

Recently governments and universities in many South American countries have shown considerable interest in a planned and orderly development of available water resources. A case in point is the preliminary study reported in which the problem is approached by utilizing a general mathematical model of the hydrologic system. Specifically, the study involves simulation by means of an electronic analog computer of the hydrology of the Paez-Pedraza region of south western Venezuela. The various processes within the model are linked by the continuity-of-mass principle, which requires a hydrologic balance at all points. The analog computer is ideally suited to the solution …


Simulation Of The Hydrologic-Economic Flow System In An Agricultural Area, Murland R. Packer, J. Paul Riley, Harold H. Hiskey, Eugene K. Israelsen Jan 1969

Simulation Of The Hydrologic-Economic Flow System In An Agricultural Area, Murland R. Packer, J. Paul Riley, Harold H. Hiskey, Eugene K. Israelsen

Reports

Like the allocation of water resources among water users, the distribution of allocated water to the subusers requires an estimate of the economic costs and benefits from a number of distribution alternatives. The most satisfactory solution maximizes the benefit cost ratio. This study is based on the premise that equitable water distribution to agricultural subusers can be more easily accomplished through the use of a technique to predict the marginal value of agricultural water. A hydro-economic model is formulated to distribute the water supply to the crops and to determine the unit value of water for the given supply. By …


The Effect Of Sediment Properties Of An Ultrasonic Plane Wave, G. H. Flammer, N. E. Stauffer Jr., E. Y. Liu Jan 1969

The Effect Of Sediment Properties Of An Ultrasonic Plane Wave, G. H. Flammer, N. E. Stauffer Jr., E. Y. Liu

Reports

No abstract provided.


A Theoretical Study On The Interpretation Of Resistivity Sounding Data Measured By The Wenner Electrode System, Siew Hung Chan Jan 1969

A Theoretical Study On The Interpretation Of Resistivity Sounding Data Measured By The Wenner Electrode System, Siew Hung Chan

Doctoral Dissertations

"This thesis deals with a theoretical study on the interpretation of resistivity sounding data measured by the Wenner electrode system. The objectives of this investigation are twofold: (i) to derive from the apparent resistivity data some suitable functions from which the resistivity and thickness of each member of the sequence of layers composing the earth may be determined, and (ii) to devise suitable methods for analyzing the resulting functions. In this investigation it is shown that the solution of the boundary value problem associated with an n-layered earth model leads to an integral equation for the Wenner electrode system. This …


An Optimization Approach To Well Spacing For Gas Storage Reservoirs, Jagannath Rao Ghole Jan 1969

An Optimization Approach To Well Spacing For Gas Storage Reservoirs, Jagannath Rao Ghole

Doctoral Dissertations

"A finite approximation to the conventional diffusivity equation describing compressible fluid flow through porous media has been developed with a view to apply it to the problems of optimum well spacing. An equilateral grid system has been employed to enable uniform well spacing for any number of wells. A numerical model has been developed on an IBM 360 - Model 50 computer, which simulates the pressure and saturation transience in the reservoir due to production impulses. This model has been used to maximize with respect to number of wells, the minimum well bore pressure reached throughout the specified withdrawal schedule. …


Mass And Heat Transfer Through Nonwettable Porous Membranes, Chung-Liang Yeh Jan 1969

Mass And Heat Transfer Through Nonwettable Porous Membranes, Chung-Liang Yeh

Doctoral Dissertations

"Evaporation of water through nonwettable porous membranes has been studied under various pressures with various membrane thicknesses. The results of previous investigations at 1 atmosphere have been correlated into one equation for mass transfer resistance which has also been found to fit approximately new data obtained of 1.5, 2, and 3 atmospheres in this investigation. In the new data fluxes varied from 0.064 to 0.691 lb./ft.²/hr. through glass fiber-Teflon membrane from 0.02 to 0.08 inch in thickness. Temperatures ranged for 80 to 260°F. A more theoretical equation has been developed to explain variations from the equations based on 1 atmosphere …


Numerical Inversion Of The Laplace Transformation And The Solution Of The Viscoelastic Wave Equations, Abbas Ali Daneshy Jan 1969

Numerical Inversion Of The Laplace Transformation And The Solution Of The Viscoelastic Wave Equations, Abbas Ali Daneshy

Doctoral Dissertations

"In the numerical inversion of Laplace transform two general techniques of inversion are analyzed; a study of the procedures based on an expansion of f̄(s) by a polynomial in 1/s (Salzer's method) provides accurate results for certain ranges of t. A curvature criterion for the selection of the range of points for polynomial interpolation, and a geometric distribution in this interval markedly improves the range and the degree of accuracy of inversion. The results may be further improved by multiplying f̄(s) by 1/s of 1/s². Other procedures are based on approximation of f̄(t). This investigation includes a general review of …


Numerical Simulation Of Pressures In A Radical System, Vijender Nath Gopal Jan 1969

Numerical Simulation Of Pressures In A Radical System, Vijender Nath Gopal

Masters Theses

"The time-space location of an advancing front has been described in such a manner as to permit the calculation of frontal pressures when a heterogeneous (in permeability) radial system is subjected to water encroachment. A finite difference application has been developed to calculate these pressures at specified radial distances from the injection or production wellbore. These pressure have been further utilized to predict the pressures at the advancing front for different time intervals"--Abstract, page iii.


Anodic Behavior Of Semiconducting Insb Single Crystals In Acidic Solutions, Lih-Da Hu Jan 1969

Anodic Behavior Of Semiconducting Insb Single Crystals In Acidic Solutions, Lih-Da Hu

Masters Theses

"Undoped, semiconducting single, n-type, InSb crystals were used to study the different etching behavior of the inverse {111} planes, to determine the apparent electron number of InSb under anodic dissolution (which corresponds to the sum of the absolute values of the oxidation numbers) and to investigate whether or not the inverse {111} planes show potential differences. The In {111}, Sb {111[repeating]}, {110} and {100} faces were highly polished, etched and immersed in various acidic solutions. Several new etch patterns of the inverse {111} faces were observed in giving other possibilities to distinguish both of the planes. The significant differences in …


Numerical Simulation Of One-Dimensional Three-Phase Fluid Flow In A Stratified Petroleum Reservoir With No Cross-Flow, Ali Mohammed Akbar Jan 1969

Numerical Simulation Of One-Dimensional Three-Phase Fluid Flow In A Stratified Petroleum Reservoir With No Cross-Flow, Ali Mohammed Akbar

Masters Theses

"A numerical model for linear, three-phase fluid flow in a stratified petroleum reservoir has been developed for the purpose of studying water-flooding performance characteristics. Gravity forces, capillary pressure and cross-flow were neglected, but the fluids were considered compressible and evaluations of dissolved gas concentrations have been accounted for. The model was used in evaluating the performance of a water flood project for a hypothetical reservoir which contained the three phases of oil, gas, and water. The results were then compared with those obtained using the Dykstra-Parsons technique. The model produces results which were found to be similar to those obtained …


The Anodic Dissolution Of Molybdenum In Alkaline Solutions, Chen Hwei Chi Jan 1969

The Anodic Dissolution Of Molybdenum In Alkaline Solutions, Chen Hwei Chi

Masters Theses

"Details concerning the anodic dissolution of many metals in various solutions are still unknown. Discrepancies are found between the actual weight-loss of an electrode and that calculated from coulometric data. The purpose of this investigation was to study the anodic dissolution of molybdenum (Mo) in basic solutions to determine the apparent valence of Mo ions going into solution, the nature of any surface films formed during dissolution, and the polarization behavior. Three electrolytes were used: 1 N potassium hydroxide (pH = 13.6), 0.667 N potassium carbonate (pH = 11.5), and potassium carbonate-potassium sulfate mixture (pH = 9.5). chloride ion additions …


Free-Convection Heat Transfer From An Inclined Heated Flat Plate In Air, S. C. Yung, R. B. Oetting Jan 1969

Free-Convection Heat Transfer From An Inclined Heated Flat Plate In Air, S. C. Yung, R. B. Oetting

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.


Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh Jan 1969

Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study concerns rates of evaporation and mass transfer of water vapor from a heated salt solution through a water repellent porous membrane to a cooled water condensate. This transfer is a result of temperature differences and corresponding vapor pressure differences across the membrane. Three groups of experiments were carried out which indicate that the major factor influencing the rates of transfer is diffusion through a stagnant gas in the membrane pores. However, an equation considering film heat transfer coefficients, membrane thermal conductivity, and an empirical correction based on temperature driving force appears to be necessary for representing all the …


Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro Jun 1968

Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro

Theses

The effect of column diameter on the frequency response of water fluidized beds was investigated.

Studies were made on four columns ranging from four to ten inches in diameter. Water was used to fluidize the beds which consisted of spherical glass beads .0185 inches in diameter. A trace solution of sodium chloride was sinusoidally introduced into the beds. Inlet and outlet concentrations were continuously measured by an electrical conductivity recorder. Separate frequency response tests were conducted on the inlet calmning section in an attempt to obtain the frequency response of this region alone. Results of the tests were expressed as …


A Study Of The Properties Of The Biconical Antenna, Kurt Frank Hafner Jr. May 1968

A Study Of The Properties Of The Biconical Antenna, Kurt Frank Hafner Jr.

Theses

Expressions are found for the fields produced by TM and TEM modes along a finitely conducting biconical antenna. Expressions are also found for the TM and TEM fileds along a biconical antenna having a lossy dielectric coating. It is shown that the antenna losses produce an anntenuation of the the fields along the antenna. It is found that because there is a dispersion of the fields along the biconical antenna, the attenuation produced by the losses is, in genaral, not characterized by simple exponential.

A solution is obtained for the fields of the TEM wave along a biconical antenna coated …


Test 973: Ford 8000 (Diesel), Nebraska Tractor Test Lab May 1968

Test 973: Ford 8000 (Diesel), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …


The Gaussian Mode In Optical Resonators With A Radial Gain Profile, Lee W. Casperson, Amon Yariv May 1968

The Gaussian Mode In Optical Resonators With A Radial Gain Profile, Lee W. Casperson, Amon Yariv

Electrical and Computer Engineering Faculty Publications and Presentations

The dependence of the parameters of the Gaussian mode in laser resonators on the properties of the medium in the cavity is studied. Experimental verification of the theoretical results is presented. It is found that the modes in a high‐gain laser may differ widely from the usual free space resonator results. Also, resonator configurations which in free space are unstable may, with a suitable medium, support low‐loss Gaussian modes.