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排序方式: 共有1173条查询结果,搜索用时 15 毫秒
71.
线与线之间的空间拓扑关系组合推理 总被引:4,自引:0,他引:4
在空间拓扑关系组合描述的基础上,进一步完善了利用基本空间拓扑关系进行组合推理的方法。并建立了组合表。详细绘制了两条线之间的空间拓扑关系图。 相似文献
72.
Ezio Faccioli 《Bulletin of Earthquake Engineering》2006,4(4):341-364
The main features of the Risk-UE project approach to assessing the ground-shaking (and related hazards) distribution within urban areas are described, as a basis for developing seismic damage scenarios for European cities. Emphasis was placed in the project on adoption of homogeneous criteria in the quantitative treatment of seismicity and in constructing the ground-shaking scenarios, despite wide differences in amount and quality of data available for the cities involved. The initial steps of the approach include treatment of the regional seismotectonic setting and the geotechnical zonation of the urban area, while the hazard assessment itself takes the form of both a deterministic analysis, and of a probabilistic, constant-hazard spectra analysis. Systematic 1D site response analyses were used, mostly in the softer soil zones, to modify (when needed) the obtained ground motion maps. Earthquake induced hazard effects, such as liquefaction and landsliding, are also briefly dealt with at the end. 相似文献
73.
74.
地震安全性评价工程师资格考试大纲已审定通过 总被引:12,自引:0,他引:12
把美国西部地区作为参考区,采用我国地震动参数区划图工作时所使用的美国西部地区强震资料建立参考区水平向基岩短周期加速度反应谱衰减关系;采用美国南加州地区数字宽频带记录建立参考区水平向基岩长周期加速度反应谱衰减关系。与由丰富的等震线资料统计得出的我国东部地区和西部地区的地震烈度衰减关系一起,用转换方法分别得到了我国东部和西部地区水平向基岩加速度反应谱衰减关系。对该衰减关系在重大工程地震安全性评价工作中的应用提出了建议。 相似文献
75.
76.
FBocchio 《Geophysical Journal International》1998,133(1):207-208
The potentialities of the so-called 'Poisson relation', which holds for uniformly magnetized bodies of constant density, for showing the connections between the gravitational and the magnetic fields of such bodies are considered. In particular, it is seen that the same characteristic ratios occur among the components of the magnetic field intensity and the components of the gradient tensors of the two fields, both locally and non-locally. It is also shown that along the magnetization axis of the body the gradient tensor of the magnetic field displays a 'tidal' structure. 相似文献
77.
SHEN Shouchang 《国际泥沙研究》1998,(3)
THECONSTITUTIVERELATIONOFDEBRISFLOW1SHENShouchang2ABSTRACTInordertoinvestigatethestresconstitutiverelationofdebrisflow,theexp... 相似文献
78.
A nonlinear magnitude frequency equation has been derived in this paper on the assumption that all seismicity systems hold
fractal characteristics, and according to the differences of relevant coefficients in the equation, seismicity systems are
classified into two types: type I, the whole earthquake activity is controlled by only one great unified system; type II,
the whole earthquake activity is controlled by more than one great system. One type of seismicity system may convert to the
other type, generally. For example, a type I system will change to a type II system prior to the occurrence of a strong earthquake
in North China. This change can be regarded as an index for earthquake trend estimation. In addition, the difference between
b value in nonlinear magnitude frequency equation and that in linear equation and the term dΔM related to the coefficients of nonlinear terms obtained in this paper are proved to be a pair of available parameters for
medium short term earthquake prediction. 相似文献
79.
Two deep-sea cores in the northwest Pacific have been analysed for sedimentology, mineralogy and environmental magnetism.
The results show that after eliminating the interference from volcanism, several proxies such as quartz content, mass susceptibility
and anhysteretic magnetic remanence can be used to indicate the eolian deposit from East Asia, and provide information on
paleo-atmospheric circulation. A comparison of eolian record in Cure RC10-175 with its oxygen isotopic curve has revealed
that the peaks of eolian accumulation occurred at the climatic “optimum” of the Holocene and the last interglaciation, showing
the fairly complex nonlinear relationship between continental/pelagic eolian records and the global glacial cycles as well
as within the climatic and environmental system.
Project supported by the National Natural Science Foundation of China (Grant No. 9291104) 相似文献
80.
河西走廊东部甜菜含糖量预测模式 总被引:1,自引:0,他引:1
运用灰色系统理论中的关联度方法,分析影响武威黄羊镇糖厂含糖量的气象因素,并建立了不含导数项的线性静态模式。经残差修正后,预测精度达98.11%。 相似文献