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991.
992.
Zdeněk Švestka 《Solar physics》1987,108(2):411-414
A simple method is proposed for a computation of the cooling of coronal flare loops by radiation and conduction, for various temperatures, densities, and lengths of the loops. The relative importance of conductive and radiative losses is briefly discussed. 相似文献
993.
Zoran Knežević 《Celestial Mechanics and Dynamical Astronomy》1986,38(2):123-138
The secular variations of the orbital elements of principal planets are calculated by means of classical Lagrange's method. The terms of the second order with respect to mass, introduced by Hill (1897) and Brouwer and van Woerkom (1950), have been taken into account as well. The best contemporary values of planetary masses and mean elements (Bretagnon, 1982) served as the starting data set for this calculation. Considerable differences with respect to previous solutions of the same type (Brouwer and van Woerkom, 1950: Sharaf and Boudnikova, 1967) were found in the coefficientsA
55,A
56, andA
66 of the system of equations of variation of elements and in the roots (frequencies)r
5 andr
6. Results are compared with some higher order/higher degree solutions and their accuracy discussed. It is confirmed that the solutions like that of Brouwer and van Woerkom, although not being completely inferior to all higher order/higher degree ones, can be considered as the first approximation only. Hence, they should be replaced by more accurate ones (Duriez, 1979: Bretagnon, 1984: Laskar, 1984) in the future applications. 相似文献
994.
995.
Burazer Nikola Šajnović Aleksandra Kašanin-Grubin Milica Radisavljević Marija Jovančićević Branimir 《Journal of Paleolimnology》2021,66(3):187-205
Journal of Paleolimnology - The study investigated the influence of maturity, biomass type, and depositional settings on the distribution and relative abundance of polycyclic aromatic hydrocarbons... 相似文献
996.
Summary The possibility of solving the stationary heat equation with the convective term is demonstrated in the case that the velocity field of the continuum, and the temperature and heat flow on the Earth's surface are known, and that an assumption is made about the magnitude of heat flows on another part of the boundary of the two-dimensional region being investigated, whereas no boundary condition is imposed on the remainder of the region's boundary. The problem has been solved numerically for a kinematic model of the lithosphere in the region of mid-ocean ridges, based on the assumption of a broad deflected convective flow moving at a distance of more than about 150 km from the ridge modelled as a plate.
aaa m u maua au na mna a, ¶rt;a um n m mua u a nmu u um mnama u mn nm. a ¶rt; amuau aamua ¶rt; amu ¶rt;um n¶rt;nu uu mn nma a a ma amuau a u a¶rt;a. ma na a u m¶rt; a ¶rt; uamu ¶rt;u um amu ¶rt;u-auu m, a a n¶rt;mauu u ma mu nma a amu m ma nau 150 ¶rt;u auma nm.相似文献
997.
Lothar Dresen Jan Kozák Aleš Špičák Ludvík Waniek Roman Teisseyre Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1984,28(3):272-285
Summary The propagation of seismic waves in a micromorphic body, which is supposed to be one of the possible models of the medium in the earthquake focus, is studied by means of the two-dimensional ultrasonic model technique. The results obtained indicate that such a medium is characterized by distinct elastic anisotropy and by increased attenuation. The propagation velocity of longitudinal waves decreases and their amplitudes change considerably. The prevailing frequency of the waves passing through the micromorphic medium tends smoothly to one value which depends on the space distribution, orientation and dimensions of the elements characterizing such a medium. The obtained results are confronted with the theory of a micromorphic medium.
anmau uu u ¶rt;, n muu ¶rt; u ¶rt; ¶rt; a mu, uam nm ¶rt; ma ¶rt;uau. mam naam, m maa ¶rt;a muam n aumnu u n nu. m anmau n¶rt;u n¶rt; nuam, u anum¶rt; m. a¶rt;aa amma , n¶rt;u u ¶rt;, na mum ¶rt; uu, ma aa nmam an¶rt;u, anam u aau ¶rt;m, n¶rt;u m ¶rt;. mam auam mu u ¶rt;.相似文献
998.
um nu-mau m nuuau u auumu m nm ma u. m mu u¶rt;uu¶rt;a m ma nuua u uu. 相似文献
999.
Summary On the basis of the conservation of the Earth-Moon angular momentum, the period of the Earth's resonance rotation and Moon's revolution and the relation between tidal deceleration of the Earth's rotation and of the Moon's mean motion are derived theoretically. The comparison of the theoretical relation with the observed values indicates that a mechanism should exist which decreases the maximum principal moment of the Earth's inertia bydC/dt=–3.2×1029
kg· . m2 cy–1.
¶rt; u au ma uma ¶rt;uu um -a, ¶rt;am mmuu ¶rt; a nu¶rt;a au u u uma ¶rt;uu u mu nuu u mu au u u ¶rt; ¶rt;uu . aua mmu mu a¶rt;au auu, ¶rt;am au, m ¶rt; um m u aua ma uuu udC/dt=–3,2×1029 2 (mmu)–1.相似文献
1000.
Lubomír Kubáček Ludmila Kubáčková Reviewer F. Štulajter Reviewer G. Siráň 《Studia Geophysica et Geodaetica》1986,30(1):1-12
Summary A procedure for processing measurements subject to systematic effects is derived such that it ensures their optimum elimination in the results of the processing. It is proved that no other method of eliminating systematic effects yields better results.
u¶rt; m¶rt; amu ¶rt;u umamuuu uuaamuu u nmua uuau mama. aa m uau ¶rt;u m¶rt; uuauu umamuu uu num u mam.相似文献