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991.
Jaroslav Střeštík Karel Prikner Reviewer M. Hooždara 《Studia Geophysica et Geodaetica》1977,21(2):159-167
Summary The numerical method of Fourier's spectral analysis is used to treat 29 pairs of samples of pc3 pulsations recorded at the observatories of Budkov (Czechoslovakia) and Belsk (Poland). The amplitude, frequency and phase characteristics of their spectra are compared. The polarization characteristics of the spectral frequency components of pulsations recorded at both observatories are compared in a quasi-stationary approximation of a plane oscillation. 相似文献
992.
Jaromír Janský Libuše Ruprechtová Bernd Tittel Reviewer K. Pěč 《Studia Geophysica et Geodaetica》1977,21(3-4):267-273
Summary PKP-amplitudes of about 400 earthquakes from the SW Pacific Ocean observed at three stations in Central Europe were used to obtain the calibration function qPKP(D, h) based on the NEIS mb magnitudes. The calibration function allows us to determine the magnitudes for week earthquakes from the Pacific, for which the magnitudes from the P-waves cannot be derived. 相似文献
993.
Summary The method of two-component spectral analysis is described in two versions: as the so-called static analysis, in which the pulsation sample being studied is treated as a whole, and as the dynamic analysis, in which the given sample is processed piecewise in order to determine the time variations of various parameters. Both versions were applied to geomagnetic pi2 pulsations. The pi2 oscillations are resolved into several frequency components. The properties of these components are studied in dependence on the frequency and local time. The time variation of the amplitude (attenuation) and the polarization characteristics (precession) of pi2's are also studied. 相似文献
994.
Zusammenfassung Die Arbeit berichtet über den heutigen Zustand und die Perspektiven der Untersuchungen der Pulsationsindizes der geophysikalischen Aktivität. 相似文献
995.
Summary The difference between the rotational time UT1 and atomic time scale AT was analysed in order to find the secular and periodic variations in the rotational velocity of the Earth. It was found that the length of the mean solar day was increasing by 12.8 ms per century in the interval discussed. As a whole, eleven periodic terms were found, the most significant having the periods of 0.5, 1.0, 6.7 and 11.9 y. The correlation between the long period changes in the Earth's rotation and relative sunspot numbers is shown. 相似文献
996.
Vlastislav Červený Věnceslava Pretlová Reviewer I. Pšenčik 《Studia Geophysica et Geodaetica》1977,21(3-4):248-255
Summary Standard methods of interpolating the velocity-depth distribution v=v(z) do not guarantee the continuity of the first and second derivatives of velocity and generate false interfaces of a higher order. These false interfaces cause anomalies in the amplitude-distance curves. It is suggested to apply the smoothed spline approximation to the depth-velocity distribution z=z(v). In this case, the ray integrals can be evaluated in a closed form. The amplitude-distance curves become quite smooth and stable. All necessary formulae and numerical examples are presented. 相似文献
997.
998.
ama nm u nmam nuau aamumuuaum nau muna Pc4 n ¶rt;a u mauu m, a¶rt; a m m anam ¶rt;u amu u¶rt;a umu. n¶rt;a auum nu¶rt;a u anum¶rt; nau u u nuau aamumu mu ¶rt; u m aum amumu, u au uu m¶rt; naam. mam auam mamau amu nau Pc3 u Pi2 n ¶rt;a u mau ¶rt; u u. 相似文献
999.
¶rt;aam ¶rt;a m¶rt;a amu uaa, u u , u auam u ma mum nuu ¶rt; uau aumma. u n u ama u ma n¶rt; ma m¶rt;a nm a umam u naa u ¶rt; nuu. mm m¶rt; n au auu u aau n¶rt;mam a au nm aum nu m unu a a. 相似文献
1000.