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A STUDY ON THE VARIATIONS OF CIRCULATION PATTERN IN THE NORTHERN HEMISPHERE AND CLIMATE CHANGE IN CHINA FOR THE RECENT 100 YEARS 
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下载免费PDF全文 The time series of annual frequency of the circulation patterns W,C,E in the Northern Hemisphere and annual mean temperature of Beijing (TB),Shanghai (TS) and the whole country (TC) in the period 1891-1990 are expanded as a long-term tendency,a periodic function and a random function.The coherence between circulation and temperature is calculated and analyzed.The abrupt change of circulation and temperature in the last 100 years is revealed with the methods of the accumulated anomalous curves,the signal/noise ratio as well as the Mann-Kendall test.The correlations between anomalous circulation and climate are discussed with some explanations. 相似文献
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Beverley J. Moore 《Geophysical Journal International》1993,115(3):1137-1142
The total Green's function for two-point boundary-value problems can be related to the propagator for initial-value problems. A very simple expression for the Green's function is obtained when the unperturbed medium may be described by material with a constant gradient in quadratic slowness. The derivation requires a correct understanding of assumptions made in the propagator solution. Expressions are also obtained for Green's function in multilayered media. 相似文献
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Dispersion of Rayleigh-type surface wave is studied in a homogeneous transversely isotropic elastic layer overlying a nondissipative liquid-saturated porous solid half-space and lying under a uniform layer of homogeneous liquid. The frequency equation in the form of ninth-order determinant is obtained.Special cases have been deduced by reducing the depth of the layers to zero and by changing the transverse isotropic layer to an isotropic layer. Dispersion curves for the phase velocity have been plotted for a particular model. 相似文献
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This paper presents an analysis of Hagen-Poiseulle flow through plane random anisotropic networks of interconnected channels. Macroscopic permeability tensor of the network is expressed in terms of statistico-geometrical characteristics like the degree of anisotropy in channel orientations, average co-ordination number of the network and first two moments of channel length distribution. Analytical results are illustrated and verified using numerical analysis of flow in a simulated random network. The emphasis of the paper is on the effects of anisotropy on distributions of flow rates in channels. It is shown that, due to anisotropy the maximum flow rate generally occurs in channels that are not aligned along the direction of the macroscopic pressure gradient. 相似文献