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481.
M. A. Anastassiades L. N. Carapiperis N. K. Kariambas P. G. Paraskevopoulos 《Pure and Applied Geophysics》1962,52(1):143-152
Summary In this study the different forms of the electromagnetic field strength recordings at the Thera-Crete microwave line of link are examined, in comparison with the corresponding weather situations prevailing over that area. According to the amplitude of fluctuations, the different forms of recordings have been classified in three basic typesA, B, C and the annual frequency of the appearance of these types has been observed. Finally, the influence of weather situations on radio wave propagation was examined and it has been found that in most cases a close relationship exists between weather situations and the different fading forms of the electromagnetic field so that a prediction of the fading form be possible by means of the weather forecast.This study was sponsored by a research grant from NATO's Scientific Committee. 相似文献
482.
483.
S. Miyamoto 《Planetary and Space Science》1960,2(4):256-260
This interpretation of lunar surface features is based on the differentiation of siliceous and basaltic substances similar to those of the earth. Our hypothesis is that lunar maria are composed of basaltic matter similar to that of terrestrial ocean basins, and that the lunar continents (bright regions) are composed of siliceous blocks. 相似文献
484.
Dr. S. Hastenrath 《Pure and Applied Geophysics》1963,56(1):225-231
Zusammenfassung Der Tagesgang von Temperatur und Luftfeuchtigkeit in San Salvador zeigt deutliche jahreszeitliche Verschiedenheiten, die wesentlich durch Strahlungsgenuss, Sonnenauf- und Untergangszeiten und ein tageszeitliches mittelräumiges Windsystem bestimmt ist.
Summary The daily variation of air temperature and humidity shows clear seasonal differences, which are essentially determined by incoming radiation, sunrise and sunset and a diurnal meso-scale wind system.
Resumen El transcurso diurno de la temperatura y de la humedad del ambiente en San Salvador demuestra netamente diferencias segun la estación del año, las cuales se deben a las condiciones de radiación, salida y puesta del sol y un sistema diurno de viento.相似文献
485.
Victor P. Starr 《Pure and Applied Geophysics》1963,56(1):163-173
Summary Equations for the motions in a galaxy which is controlled by gravitational forces and inertial effects are formulated. It is found that for the motions relative to the rotating system formulae analogous, and of similar form, to the geostrophic wind equations may be written. From these formulae and from the distribution of the relative gravitational potential in the disc of the galaxy, it is found that a spiral tendency in the mass distribution carries the implication of an inward flux of angular momentum by advective processes. This is to be compared with an outward flux through gravitational torques obtained in previous studies in which the writer participated. 相似文献
486.
Victor P. Starr 《Pure and Applied Geophysics》1963,56(1):159-162
Summary A gradually cumulative error due to the use of the hydrostatic approximation is examined through consideration of a simple mathematical model taken from the classical theory of gravity waves. Two cases are chosen which differ solely in the circumstance that in one the hydrostatic assumption is made while in the other it is not. A large divergence of the results present in the later stages is then to be referred to the neglect of terms contained in the exact equation of motion for the vertical direction in one of the solutions. The inference is drawn that comparable phenomena might arise in the integration of the atmospheric equations over long time periods. 相似文献
487.
488.
The motion and the drift force of a floating OWC (oscillating water column) wave energy device in regular waves are studied taking account of the oscillating surface-pressure due to the pressure drop across the duct of the air chamber. The potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine-type Green function while the outer problem with the Kelvin-type Green function. The added mass, wave damping and excitation coefficients as well as the motion and drift force of the OWC device are calculated for various values of parameter related to the pressure drop. 相似文献
489.
Numerical simulation of undersea cable dynamics 总被引:7,自引:0,他引:7
A fully three-dimensional code has been written to compute the motion of a towed cable. The code is based on a robust and stable finite difference approximation to the differential equations derived from basic dynamics. A 3500-ft (1.07 km) cable pulled at 18.5 knots (34.3 km hr−1) through a circular turn of 700 yd (0.64 km) radius has been computed in about half of the real time of the maneuver. The computed displacements are close to the measured ones; the changes in depth are within 2%. 相似文献
490.
Louis I. Gordon P. Kilho Park Stephen W. Hager Timothy R. Parsons 《Journal of Oceanography》1971,27(3):81-90
Observations were made of time variations of the carbon dioxide partial pressures (Pco2) of the atmosphere and surface sea waters in the Pacific subarctic region. Data were obtained on a cruise of the USC & GSSSURVEYOR in October, 1968 and on the TRANSPAC expedition of the CNAVENDEAVOUR in March–April, 1969. A rise in surface water Pco2 of 18×10–6 atm occurred in a period of 30–45 days in March–April due principally to spring warming of surface waters. An average increase of 60×10–6 atm occurred between October, 1968 and March, 1969 as a result mainly of cessation of summer phytoplankton production and the onset of winter-storm-driven vertical mixing. Because the air-sea Pco2 gradient not only changed appreciably in magnitude but also changed sign, there are important implications for calculations of air-sea exchange of carbon dioxide on the ocean wide scale.Data contained in this paper comprise part of a dissertation to be submitted by Louis I. Gordon in partial fulfillment of the requirements for the Ph. D. at Oregon State University. 相似文献