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Rotationally Symmetric Potential Flows

Description: This paper includes the following topics: 1) Characteristic differential equations; 2) Treatment of practical examples; 3) First example: Diffuser; and 4) Second Example: Nozzle.
Date: November 1949
Creator: Schäefer, Manfred & Tollmien, W.
Partner: UNT Libraries Government Documents Department

Acoustics of a Nonhomogeneous Moving Medium

Description: Report discussing theoretical basis of the acoustics of a moving nonhomogeneous medium. Experiments that illustrate or confirm some of the theoretical explanation or derivation of these acoustics are also included.
Date: February 1956
Creator: Blokhintsev, D. I.
Partner: UNT Libraries Government Documents Department

Some Diophantine Equations

Description: This paper will be devoted to an examination of several general and specific equations and systems of equations of the diophantine type. Only algebraic equations with integral coefficients, not all zero, will considered. The elementary properties of the integers will be assumed.
Date: January 1960
Creator: Pressly, Kirby Smith
Partner: UNT Libraries

Energy Dissipation by Fast Electrons

Description: Report discussing the energy dissipated by fast electrons at different distances from monoenergetic electron sources, for plane perpendicular and point isotropic sources including tabulations and a summary of the theoretical methods and data utilized, and a table of spatial moments.
Date: September 10, 1959
Creator: Spencer, L. V.
Partner: UNT Libraries Government Documents Department

Influence of a Sector Ground Screen on the Field of a Vertical Antenna

Description: Report show the field of a short vertical antenna on a homogeneous ground is modified by the presence of a metallic screen. The screen is taken in the form of a circular disk and a concentric sector. The modification of the field is expressed in the form of surface integrals over the disk and the sector. Extensive numerical results for these basic integrals are given and a number of applications are illustrated.
Date: April 15, 1963
Creator: Wait, James R. & Walters, Lillie C.
Partner: UNT Libraries Government Documents Department

Refractive Indices and Densities of Aqueous Solutions of Invert Sugar

Description: Report of the refractive indices and densities of aqueous solutions of invert sugar at temperatures of 15, 20, 25, and 30º C, for concentrations up to about 82 percent of invert sugar (by weight). From the results, equations have been derived which relate the refractive index and percent of invert sugar (weight in air) at each temperature. Other equations relate the absolute density and percent of invert sugar (weight in vacuum) at each temperature. Five-decimal tables giving the refractive indices and densities of invert sugar solutions containing 1 to 85 percent of sugar are given for each percentage of invert sugar at the four temperatures.
Date: June 7, 1963
Creator: Snyder, Carl F. & Hattenburg, Albert T.
Partner: UNT Libraries Government Documents Department

Thermal Expansion of Technical Solids at Low Temperatures: A Compilation From the Literature

Description: Report giving tables of the linear contraction relative to 293 ºK, (L293ºLT)/L293, and the linear expansion coefficient, dL/L293dT, of thirty elements, forty-five alloys, twenty-two other inorganic substances and twenty plastics and elastomers in the temperature range, 0 to 300 ºK.
Date: May 19, 1961
Creator: Corruccini, Robert J. & Gniewek, John J.
Partner: UNT Libraries Government Documents Department

Microwave Impedance Measurements and Standards

Description: Report presenting a survey and discussion of well-known microwave impedance measurement techniques. The discussion includes an introduction which emphasizes basic concepts and reflection coefficient-voltage standing-wave ratio relationships. Sources of error in the various measurement techniques are discussed and methods to reduce errors are presented. Methods using rotating loops and resonance lines are included and a brief discussion of microwave impedance standards is given.
Date: August 12, 1965
Creator: Beatty, Robert W.
Partner: UNT Libraries Government Documents Department

A Study of Lunar Surface Radio Communication

Description: Report discussing the problem of point-to-point radio communication on the moon. Equations and curves are presented to estimate power requirements in lunar communication systems. Consideration is given to ground wave attenuation over both layered and non-layered grounds, antenna ground losses in situations where ground screens are impractical, noise level estimates in the receiving system, and the effects on propagation of possible lunar ionospheres. An example of the calculation of required power for a particular communication system is given, and further studies are suggested.
Date: September 14, 1964
Creator: Vogler, L. E.
Partner: UNT Libraries Government Documents Department

The NBS Standard Hygrometer

Description: Report describing a gravimetric hygrometer that serves as the NBS standard instrument for the measurement of the moisture content of gases on an absolute basis in terms of mixing ratio (mass water vapor/ unit mass of dry gas). The National Bureau of Standards and other laboratory reference and working instruments are compared and calibrated with this instrument. The measuring operation involves the absorption of the water vapor from a water vapor-gas mixture by a solid desiccant and the determination of the mass of this water vapor by precision weighing; it also involves the determination of the volume of the associated gas of known density by counting the fillings of two calibrated stainless steel cylinders. The construction and operation of the instrument is described. Discussions of the tests and calibrations of component parts, and of the sources of errors also are included. There is also an analysis of the random and systematic errors effecting the overall accuracy in the determination of mixing ratio.
Date: May 1, 1964
Creator: Wexler, Arnold & Hyland, Richard W.
Partner: UNT Libraries Government Documents Department

On the Statistical Theory of Electromagnetic Waves in a Fluctuating Medium (II): Mathematical Basis of the Analogies to Quantum Field Theory

Description: Report discussing the relationship between quantum field theory and the the statistical theory of waves. Basic equations exist in the latter theory which correspond closely to the fundamental equations of the former theory; i.e., to the commutation relations and the Heisenberg equation of motion. A probability density function of waves is introduced here which corresponds to the probability amplitude function in quantum mechanics. The theory of the statistical Green's functions and their relationships to the expectation values of the physical variables is also extensively developed. It is found that there exists a one-to-one correspondence between the formalism of Green's functions presented here and that used in field theory.
Date: December 7, 1964
Creator: Furutsu, K.
Partner: UNT Libraries Government Documents Department

Reduction of Data for Piston Gage Pressure Measurements

Description: Report discussing pressure measurements made with piston gages that are affected by gravity, temperature, pressure, and several other variables. For accurate determinations of pressure the calculations must take these variables into account. A general equation is developed and simplified procedures for calculating pressure are illustrated.
Date: June 17, 1963
Creator: Cross, J. L.
Partner: UNT Libraries Government Documents Department

Radio Meteorology

Description: Report compiling the work done in radio meteorology over the past ten years at the National Bureau of Standards' Central Radio Propagation Laboratory (CRPL). There is an emphasis upon the effects of the lower atmosphere on the propagation of radio waves. The CRPL group has concentrated upon the refraction of radio waves as well as the refractive index structure of the lower atmosphere on both synoptic and climatic scales. Additional chapters on radio-meteorological parameters and the absorption of radio waves by the various constituents of the lower atmosphere.
Date: March 1, 1966
Creator: Bean, B. R. & Dutton, E. J.
Partner: UNT Libraries Government Documents Department

Trajectory versus probability density entropy

Description: In this article, the authors show that the widely accepted conviction that a connection can be established between the probability density entropy and the Kolmogorov-Sinai (KS) entropy is questionable.
Date: 2001
Creator: Bologna, Mauro; Grigolini, Paolo; Karagiorgis, Markos & Rosa, Angelo
Partner: UNT College of Arts and Sciences

On Traveling Waves in Beams

Description: "The basic equations of Timoshenko for the motion of vibrating nonuniform beams, which allow for effects of transverse shear deformation and rotary inertia, are presented in several forms, including one in which the equations are written in the directions of the characteristics. The propagation of discontinuities in moment and shear, as governed by these equations, is discussed. Numerical traveling-wave solutions are obtained for some elementary problems of finite uniform beams for which the propagation velocities of bending and shear discontinuities are taken to be equal" (p. 359).
Date: October 28, 1952
Creator: Leonard, Robert W. & Budiansky, Bernard
Partner: UNT Libraries Government Documents Department

General Problem of the Airplane

Description: A series of equations relating to airplanes are given and examples listed. Some of the equations listed include: the speed, altitude and carrying capacity of various airplanes; weight of an airplane; weight of various parts of an airplane; the polars of the wings; speeds of airplanes; radius of action.
Date: July 1922
Creator: Richard, Maurice & Richard, Paul
Partner: UNT Libraries Government Documents Department

Local Instability of Symmetrical Rectangular Tubes Under Axial Compression

Description: "A chart is presented for the coefficient in the formula for the critical compressive stress at which cross sectional distortion begins in a thin-wall tube of rectangular section symmetrical about its two principal axes. The energy method of Timoshenko was used in the theoretical calculations required for the construction of the chart. The deflection equation used in this method was selected to give good accuracy" (p. 1).
Date: February 1939
Creator: Lundquist, Eugene E.
Partner: UNT Libraries Government Documents Department

Two-Dimensional Subsonic Flow Past Elliptic Cylinder by the Variational Method

Description: "A method of solution is presented for compressible fluid flow past an elliptical cylinder by means of the variational method. The solution is obtained as a function of thickness ratio and free-stream Mach number. Numerical examples are carried out for several thickness ratios and Mach numbers and the results are compared with those obtained by other methods" (p. 1).
Date: March 1952
Creator: Rao, G. V. R.
Partner: UNT Libraries Government Documents Department