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Intermediate orbit for general planetary theory is constructed in the form of multivariate Fourier series with numerical coefficients. The structure and efficiency of the derived series are illustrated by giving various statistical properties of the coefficients.The ability of the recently proposed elliptic function approach to compress the Fourier series representing the intermediate orbit is investigated. Our results confirm that when mutual perturbations of a pair of planets are considered the elliptic function approach is quite efficient and allows one to compress the series substantially. However, when perturbations of three or more planets are under study the elliptic function approach does not give any advantages.  相似文献   
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The problem of clock synchronization: A relativistic approach   总被引:2,自引:0,他引:2  
The problem of synchronization of the Earth-based clocks has been discussed in the framework of General Relativity Theory. The synchronization is considered as the transformation of the observers' proper time scales to the coordinate time scale of local inertial geocentric reference system, which is single for all the observers. The formulas for the relativistic corrections occurring in some methods of Earth-based clock synchronization (transported clock, duplex communication via geostationary satellite and meteor-burst link, LASSO experiments) have been derived enabling one to attain the accuracy of 0.1 ns.  相似文献   
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Loop Current Frontal Eddies (LCFE) in the Gulf of Mexico are simulated with a regional configuration of the Princeton Ocean Model using a feature-oriented initialization technique. The initialization procedure is based on a prior investigation of stability characteristics of the Loop Current (LC). Zonal channel experiments conducted with a multi-layer intermediate equations model allowed to identify conditions necessary for formation and growth of frontal eddies. The simulations were able to reproduce key features of LCFE-topography interaction in the DeSoto Canyon region observed during the “Eddy Intrusion” study.  相似文献   
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S. D. Nikolaev 《Oceanology》2006,46(4):513-525
The objective of this study was to present details of the evolution of the thermal field of the ocean during the last Cenozoic glacial megacycle. The main causes of the phenomena observed are discussed based on the generalization of original data accumulated during many years and numerous publications. It is shown that, in the Eocene and Early Oligocene, the climatic conditions in the World Ocean were uniform and featured no evident zonal differences, the meridional temperature gradients were low, and the mean global temperature was close to the present-day value. Starting from the Late Oligocene and throughout the entire Neogene, the meridional contrasts in the temperature and hydrological conditions have increased, and, in the Late Pliocene, the climatic pattern resembled the present-day situation. The general tendency in the climate changes since the Eocene until the Pliocene consisted of its latitudinal differentiation and growing contrasts rather than of general climate cooling. In the Pleistocene, with the onset of the glaciation in the Northern Hemisphere, the character of the temperature field changed and variations in the mean global temperature values began to dominate. The factors that result from the climate changes observed are discussed and the causes are shown that lead to the differences between the author’s data and the existing concepts.  相似文献   
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A new approximation of the real part of the nonrelativistic plasma dispersion function ?Z of a real argument ξ0 is proposed: namely, $$\Re Z_A (\xi _0 ) = \frac{{2\xi _0 }}{{1 - 2\xi _0^2 }}.$$ This approximation gives the exact value for ?Z when d2?Z/dξ 0 2 = 0 and gives the correct expressions for the first two terms of its expansion for large ξ0. On the basis of this approximation, a new approximate expression for whistler-mode refractive index is derived for the case of wave propagation parallel to the magnetic field in a hot anisotropic and dense plasma. Under certain conditions this expression is more convenient for practical applications in magnetospheric and/or astrophysical conditions than other approximate expressions. The approximation ?Z A was also used in deriving the approximate expression for whistler-mode instability or damping (γ), although in this case it seems to have little merit when compared with the previously used expressions for γ.  相似文献   
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