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861.
在对牛顿经典力学和爱因斯坦相对论对空间时间概念阐述的基础上,指出由于地壳运动是个宏观低速现象,因此完全可采用牛顿力学描述地壳质点在空间的位置以及在外力作用下该位置是如何随时间改变的,决定了必须选择一个不作加速度运动的参照系,才能正确使用牛顿定律对地壳运动进行正确的描述.因此满足牛顿惯性定律的参照系为地壳运动分析使用的坐... 相似文献
862.
2009年《海岛保护法》的颁布是我国海洋法制建设史的里程碑。为实现无居民海岛的可持续发展,必须加强对无居民海岛的保护与管理,规范开发利用秩序。法制是无居民海岛可持续发展的重要保障,健全对无居民海岛的保护立法应结合《海岛保护法》的有关规定,进一步完善无居民海岛的权属制度,建立合理利用无居民海岛的法律制度。 相似文献
863.
864.
?pik’s formulae for the probability of collision are applied to the analysis of the collision risk against space debris in Low-Earth Orbit (LEO) and Medium Earth Orbit. The simple analytical formulation of ?pik’s theory makes it applicable to complex dynamical systems, such as the interaction of the ISS with the whole debris population in LEO The effect of a fragmentation within a multiplane constellation can also be addressed. The analysis of the evolution of the collision risk in Earth orbit shows the need of effective mitigation measures to limit the growth of the collision risk and of the fragmentation debris in the next century. 相似文献
865.
DAI Dejun WANG Wei QIAO Fangli YUAN Yeli 《中国海洋大学学报(英文版)》2007,6(4):345-348
Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a – 4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the – 4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc. 相似文献
866.
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邓永和 《大地测量与地球动力学》2007,27(6):65-67
?????????????????????????????????У?????????????????Щ???????????????????????????????????????????????????????????????????????????????????????????·?????????????÷???????к???Ч??? 相似文献
867.
Altai polymetallic mineralization belt is famous copper-polymetallic mineralization belt in the world. There are a lot of gold deposits in the Altai ore belt in Xinjiang, China. These gold deposits belong to two genetic types: volcanogene late-stage hydrothermal type and fractured altered rock type. The authors discuss mainly the geological and mineralized features of fractured altered rock type of gold deposits in Altai gold ore belt. Base on this study, the metallogenic law is summarized and the deep metallogenic prognosis has been done in Duolanasayi and Tuokuzibayi gold deposits, and some mineralized anomalys have been discovered. 相似文献
868.
Sediment incipient motion is a fundamental issue in sediment transport theory and engineering practice. Whilst Shields curve often is used to determine the threshold of sediment movement under unidirectional current conditions, it is unclear whether it can be directly applied for the wave or combined wave-current conditions. The study developed adaptive criterion curves describing incipient motion of sediment under wave and current conditions based on the flow pattern around the sediment particles. Firstly, the flow pattern law for fixed particles was recognized based on the friction law under various dynamic conditions (wave, current, and their combinations), and the flow pattern demarcations for incipient sediment motion were obtained with the threshold conditions for sediment movement under various dynamic conditions combined. Secondly, the exact shape of the Shields curve in each flow regime was derived under the current condition. By combining the flow pattern demarcations for incipient sediment motion under the wave condition, the criterion curve under the wave condition was derived. By combining the flow pattern demarcations for incipient sediment motion under the combined current-wave condition, the criterion curve for sediment incipient motion under the combined current-wave condition was derived. The results indicated that the flow pattern around incipient particles includes laminar, laminar-rough turbulent transition, and rough turbulent regimes. The criterion curves for sediment incipient motion under various dynamic conditions stayed the same in the laminar and rough turbulent regimes, but different in the transition regime. Depending on the relative strengths of the currents and waves, the shape of the criterion curve under the combined current-wave condition transitions adaptively between the criterion curve under the current condition and the criterion curve under the wave conditions. 相似文献
869.
围绕北方海航道定义和破冰船强制领航两个重要的争议问题,详细对比了俄罗斯相关旧法律条文和2013年颁布的新法律条文,综合分析后认为:(1)在法律层面上,俄罗斯对于北方海航道属于国家历史性交通干线的立场没有改变,范围则做了明晰化的界定,新的北方海航道水域范围与俄罗斯北冰洋内水、领海及毗连区和200海里专属经济区水域范围相一致。这意味着消除了有关北方海航道北部边界是否延伸到公海的争议;(2)在规则层面上,从破冰船强制领航制度改变为许可证制度,尤其是给出了具体的、可操作和可预期的独立航行许可和不许可条件,使得外国船只在北方海航道水域的独立航行成为可能。由此得出结论:俄罗斯北方海航道政策出现了较大变化,有进一步向国际开放的政策倾向。 相似文献
870.