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801.
Gao Yuan Wu Zhongliang and Zhou HuilanGraduate School of USTC Academia Sinica Beijing ChinaCenter for Analysis Prediction China Seismological Bureau Beijing ChinaInstitute of Geophysics China Seismological Bureau Beijing China 《中国地震研究》1998,(3)
Four earthquakes with M > 6.0 occurred in Qinghai Province, China froth 1988 to 1990. Using broadband data from GDSN, the source ruptures of these earthquakes and tectonic surroundings were studied using waveform modelling combined with background data of geological tectonics. Through the analysis of apparent source time function (aSTF) and apparent time difference (aTD), the complexity of sources was discussed, and in view of source analysis, the result further supports the conclusion that the compressive stress axis of tectonic stress field in northeastern Qinghai-Xizang (Tibetan) plateau is at the NE direction, is nearly horizontal, turns counter-clockwise to the NEE or N to S direction, and is nearly horizontal close to the northern Qinghai-Xizang plateau. 相似文献
802.
基于公交网络模型的最优出行路径选择的研究 总被引:23,自引:1,他引:23
在讨论公交网络特性的基础上 ,基于结点 弧段 有向线描述了公交网络的数据组织 ,研究综合换乘次数及距离因素的出行路径选择模型 ,并提供算法的实现 相似文献
803.
On the basis of an electronic map-based hypermedia data model (EMBHDM),this paper makes a study on the technologies of nonlinear storage,organization,management and browsing of information,management and browing of information as well as organization of data on the basis of the relationship between multimedia information of electronic maps. This paper first analyzes some features of electronic maps and hypermedia technologty,and then illustrates the creation of EMBHDM with some examples.The tests show that this model can efficiently organize and express multimedia data. 相似文献
804.
805.
应用中国数字地震台网(CDSN)记录的长周期体波波形数据,反演了1988年11月6日中国云南省澜沧-耿马MS7.6地震的矩张量,求得了其震源机制和震源时间过程.反演结果表明,断层面解的一个节面是右旋走滑断层,另一个节面是左旋走滑断层;震源时间过程较简单,持续时间约15 s;标量地震矩为6.41020 Nm.根据地质资料、区域构造、野外观测和余震震中分布,确认走向313的节面是地震断层面,主压应力轴位于几乎水平的南北向. 相似文献
806.
Based on research on information organization and visualization mechanism of multimedia electronic map, this paper proposes an organization method about spatial information and multimedia information of multimedia electronic map: seamless spatial data were organized and managed by stratified expansion R-tree and Quad-tree hierarchy; and multimedia information data were organized and managed by hypermedia model based on an electronic map. Considering electronic map features, the paper also proposes a method for spatial date organization, which integrates Digital Landscape Model and Digital Cartographic Model, and a hybrid model between vector and raster spatial data. Then, the paper studies information visualization mechanism of multimedia electronic map. Finally, the paper certifies the results via a case of multimedia electronic map authoring tools software-Atlas2005. 相似文献
807.
基于OpenLayers的旅游地图方案研究 总被引:2,自引:1,他引:1
本文简要介绍国内最新旅游新闻动态,提出一种基于OpenLayers的多源数据整合方案,进行在线旅游地图服务,此方法定制方便灵活、开发简单,很适合中小型应用。 相似文献
808.
Xudong Zhao Huiping Zhang Honghua Lv Yuanyuan Lü Xuemei Li Kang Liu Jiawei Zhang Jianguo Xiong 《Basin Research》2021,33(1):291-311
The Chinese Tian Shan is one of the most actively growing orogenic ranges in Central Asia. The Late Miocene‐Quaternary landscape evolution of northern Tian Shan has been significantly driven by the interaction between tectonic deformations and climate change, further modulated by the erosion of the upstream bedrocks and deposition into the downstream basins. In this study, only the accessible Kuitun River drainage basin in northern Tian Shan was considered, and detrital zircon geochronology and heavy minerals were analyzed to investigate the signature of the driving forces for Miocene sedimentation in northern Tian Shan. This study first confirmed a previously recognized tectonic uplift at ca. 7.0 Ma and further revealed that the basin sediments were mainly derived from the present glacier‐covered ridge‐crest regions during 3.3–2.5 Ma. It is suggested Late‐Pliocene to Early Pleistocene sedimentation was likely a response to the onset of the northern hemispheric glaciation. Although complicated, this study highlights that the tectonic‐climatic interaction during the Late Cenozoic orogenesis can be discriminated in the northern Chinese Tian Shan. 相似文献
809.
详细介绍榆树地震台地电场观测系统的运行状况,从数据完整率、静日、扰日变化形态以及相关系数、差值等方面对观测系统运行进行综合评价,结果表明:榆树地震台地电场观测系统运行稳定可靠,能够记录到震前地电场异常变化,可以为地震预测预报研究提供一定依据。 相似文献
810.
利用广东地震台网的固定台和流动台记录的2次人工爆破事件,通过随机模拟台网几何形态,获得了该台网近震定位精度的经验性GT(Ground Truth)准则。结果表明:地震定位精度与台网几何形态密切相关;当台网满足以下条件时近震震中定位精度优于2km,震源深度精度优于3km,具有95%的置信度:(1)震中距小于150km的台站数≥7;(2)一级方位角空区<180°;(3)震中距小于10km的台站数≥1。在评估震源深度精度时,发现对于壳内地震,可靠的近台数据能够提高震源深度的精度,而定位时震中距较大的台站数量的增加对震源深度的精度影响很小。最后,应用该GT准则对广东地震台网产出的地震观测报告进行了评估,获得了1160个GT2参考事件。 相似文献