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891.
Summary A method is proposed for determining the precise shape of the isolines, corresponding to any continuous and non-constant function of two variables. The co-ordinates of the points of the isolines are determined by solving numerically two ordinary differential equations of the first order which describe the isoline. A model example is given, in which the isolines of a function, determined by bicubic spline interpolation from values, given in a regular network, are found. 相似文献
892.
František Marek Reviewer F. Janák Reviewer V. Kropáček 《Studia Geophysica et Geodaetica》1971,15(1):100-104
Summary Virtual geomagnetic poles, corresponding to the directions of primary remanent magnetization of the neovolcanic occurrences studied in the Lower Jeseník, form a close group which is positionally considerably removed from the present geographic pole. By comparison with some published data on the extent of the secular variation of the geomagnetic field, a conclusion was drawn that the assumption of a practically simultaneous generation of the considered volcanites (over a period of about one third of the longest secular variation cycle) is at least twice as probable as the assumption of an expressive difference in their age. 相似文献
893.
Ohne Zusammenfassung 相似文献
894.
V. Klemeš 《Journal of Hydrology》1974,21(4):305-314
Probability distribution of output from a linear reservoir is derived for a random and a first-order Markovian input. In the first case it is expressed in terms of the input distribution, in the second in terms of the distribution of its random component. 相似文献
895.
Summary Using the data in[1], the scale factor for lengths is derived of the geopotential model R
0
=GM/W
0
(W
0
is the potential on a generalized geoid). The resulting value, R
0
==6 363 672.9 m, which is2 m less than the original value[5], is practically the same as that in[6]. 相似文献
896.
897.
Summary Three important characteristics of the stochastic relation between the position of one point of a geodetic network and the positions of the remaining points are investigated: a) Change of the ellipse of confidence of the position of a point of the network to the ellipse of confidence of the position of a point of the network, relative to any other point of the network. (This characteristic is called the change of the global ellipse of confidence to the relative ellipse). b) The regression between the positional vector of the investigated point and the positional vectors of some group of other points of the network and c) the so-called total correlation between any two points of the network. The latter characteristic is a question of determining a characteristic direction for each pair of investigated points, which would have the property that the correlation coefficient between the random displacement of the first point in its characteristic direction and the random displacement of the second point in its characteristic direction is maximum. 相似文献
898.
Karel Prikner Jaroslay Střeštík Karel Dobeš Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1973,17(4):337-345
Summary Using the method of two-component spectral analysis of planar oscillation events by means of computer processing of A-t records, a series of about 100 samples of geomagnetic beating-type pulsations pc3 was treated. The quantitative data obtained on the internal structure of the pulsations (frequency spectra and polarization characteristics) were treated statistically. The pattern of the daily variations of the frequencies and amplitudes of the fundamental amplitude-dominating frequency components of the pulsations and the daily variations of the polarization characteristics of these components, the ellipticity of the polarization ellipses, the directions of the main axes of these ellipses and the sense of rotation of the disturbance vector along the ellipses were obtained.A part of the results was reported at the XVth General Assembly of the IUGG, Moscow, August 1971. 相似文献
899.
Karel Dobeš Karel Prikner Jaroslav Střeštík Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1973,17(3):240-244
Summary A new method is presented of computer processing of amplitude-time records. The method is based on a two-component spectral analysis, suitable for investigating a planar stationary oscillatory event. The method is applied to the study of the fine structure of short-period geomagnetic pulsations. Apart from a semi-quantitative representation of the directional distribution of the pulsation event in the plane of oscillation, the proposed method enables one to obtain quantitative information on the frequency components, representing the pulsation — the distribution of the overall energy in the spectrum of the pulsation, the ellipticity of the polarization ellipses, the orientation of the major axes of the ellipses, and the sense of rotation of the disturbance vector. 相似文献
900.
Summary The potential energy of the Earth—Moon system is derived and, thus, also the disturbing potential function, responsible for the lunar precession of the Earth's axis, with preserving the terms from the non-spherical disturbing body. The gravitational fields of the Earth and Moon are considered in the form of a development in terms of spherical harmonics upto n=4. 相似文献