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501.
Based on a zonally non-uniform mean circulation in summer simulated by numerical modelling,perturba-tion heatings ever South Asia and a perturbation cooling over Northwest Australia were incorporated in a nu-merical model to discuss their effects on summer monsoon over Asia and the structure of flow disturbance. 相似文献
502.
大同—阳高地震烈度宏观考察组 《山西地震》1991,(3):18-30
文中叙述了大同—阳高地震区的烈度划分原则、烈度分布范围、烈度异常情况,给出了宏观地震参数(h=11.2km,震级5.8M_L),指出宏观调查的烈度值与强震仪记录的强余震加速度基本一致。 相似文献
503.
504.
The favourable synoptic situation and climate background for a sandstorm process,which occurred in theperiod 9—16 April 1988,have been studied through analyzing weather maps,meteorological elements,satellitecloud pictures and sandstorm trajectories.The sand dust origin area,the directions and the paths of sanddust transport,and the extent the sand dust reached are also investigated.The results of measurments andanalysis indicate that the concentration of sand dust particles is 10 times greater than the normal.It is also shownthat the elements in the sand dust are lithophylic and come from natural source through the chemical composi-tion analysis of the sand dust,so that the sand dust has not been polluted by human activities. 相似文献
505.
NUMERICAL EXPERIMENT OF THE INFLUENCES OF HEAT AND WIND STRESS ON THE EQUATORIAL OCEAN CIRCULATION 总被引:1,自引:0,他引:1
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A time-dependent linear model on the equatorial beta plane is developed in this paper.Its verticalstructure consists of two active layers with equal density and temperature above the thermocline and aquasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean ismuch smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibriumand anomalous development of the ocean-almosphere circulation. 相似文献
506.
空间测边交会的解法、精度估算和最佳图形探讨 总被引:2,自引:0,他引:2
本文介绍空间测边交会的三种解法。利用矩阵迹的性质,巧妙推出了实用的精度估算式,并由此得出空间测边交会的最佳图形为交会角皆是90°的四面体的结论。 相似文献
507.
508.
The Seismic Intensity Zoning Map of China(1990)was based on the probabilistic method of seismic hazard analysis.In compiling the map,the characteristics of inhomogeneity of earthquake distribution both in space and time in China are considered sufficiently,and some necessary modifications in the model of seismic hazard analysis are carried out.Based on the analysis of the seismic activity and seismotectonic environment,26 seismic provinces are divided first as the statistical elements of the seismicity analysis; the seismic potential source areas are then divided in the seismic provinces.The 733 potential source areas with various upper limit magnitudes have been divided in the country.According to the reliable time domain of earthquake data with various magnitude intervals,the b values in magnitude-frequency relationship are calculated in the seismic provinces.According to the analysis of the inhomogeneity of seismicity distribution both in space and time,the annual average occurrence rates of the eart 相似文献
509.
In this paper,the equivalent force inside the source which produces a large area deformation field is calculated by using the records of residual deformation,S wave radiation of shear dislocation source and Green function of the Lancang-Gengma earthquake.Under the action of equivalent force whose intensity was 1.103×1013 N,the crust derm of northeast segment of seismic fault had finished the upraise and formed permanent irrecoverable deformation within 20.46 min after the major earthquake occurred.The authors indicate that the residual deformation would split into 2 deformation fields with different propagation velocities and different directions in the Song-distance propagation process. 相似文献
510.
通过实验,对饱和粘性土的渗透规律进行研究,得到几点新认识。利用此认识建立了饱和粘性土越流补给量的计算公式,并在实际应用中得到验证。 相似文献