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221.
Krzysztof Goździewski 《Celestial Mechanics and Dynamical Astronomy》1998,70(1):41-58
In this paper we consider the problem of motion of an infinitesimal point mass in the gravity field of an uniformly rotating
dumb-bell. The aim of our study is to investigate Liapunov stability of Lagrangian libration points of this problem. We analyze
the stability of libration points in the whole range of parameters ω, μ of the problem. In particular, we consider all resonance
cases when the order of resonance is not greater than five.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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The focal mechanism solution of the M s 6.5 Wuding earthquake in Yunnan Province of October 24, 1995
The focal mechanism of Wuding earthquake with magnitude M=6.5 on October 24, 1995 is estimated by the method of inversion of seismic tensor in this paper. The two principal axes are
nearly horizontal, the principal compressive axis is about N30°E, the nodal plane which strikes about N105°E (N75°W) is probably
consistent with the actual rupture plane. 相似文献
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王同和 《吉林大学学报(地球科学版)》1988,(1)
中国东部拉张区变形期间发育的正断层,按其几何形态和运动学特征的差异,可确定为四种类型:1.非旋转平面状正断层;2.旋转平面状正断层;3.犁状正断层;4.低角度正断层或滑脱断层。它们及其组合控制着沉积盆地的外部轮廓、规模大小、沉积建造类型和内部变形以及油气构造的形成。本文综合分析了各类正断层特征及其演化过程,认为不同层次、不同尺度和不同类型正断层的发育过程,也是中国东部地壳拉伸变薄及沉积盆地的形成过程。 相似文献
229.
Repeated leveling data collected over a 14-km long traverse, crossing the Atalandi fault that last broke in 1894, revealed small amplitude motions for the interval 1969–1984. These motions are significant against random errors and are probably free of systematic errors. In addition, no local or superficial ground effect may account for the observed elevation changes which correlate with the tectonic pattern in the area, as they show a relative downward motion of the hanging wall of a normal fault. This motion is similar to the co-seismic slip. Geomorphological observations and observations of submerged archaeological sites on the other hand corroborate long-term motions which are unlikely to be explained as cumulative co-seismic slip and are possibly similar to the short-term motions leveling data reveal. 相似文献
230.
Based on the Hilbert–Huang spectral analysis, a method is proposed to identify multi‐degree‐of‐freedom (MDOF) linear systems using measured free vibration time histories. For MDOF systems, the normal modes have been assumed to exist. In this method, the measured response data, which are polluted by noises, are first decomposed into modal responses using the empirical mode decomposition (EMD) approach with intermittency criteria. Then, the Hilbert transform is applied to each modal response to obtain the instantaneous amplitude and phase angle time histories. A linear least‐square fit procedure is proposed to identify the natural frequency and damping ratio from the instantaneous amplitude and phase angle for each modal response. Based on a single measurement of the free vibration time history at one appropriate location, natural frequencies and damping ratios can be identified. When the responses at all degrees of freedom are measured, the mode shapes and the physical mass, damping and stiffness matrices of the structure can be determined. The applications of the proposed method are illustrated using three linear systems with different dynamic characteristics. Numerical simulation results demonstrate that the proposed system identification method yields quite accurate results, and it offers a new and effective tool for the system identification of linear structures in which normal modes exist. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献