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151.
地球化学场精细结构解析方案与应用 总被引:2,自引:2,他引:2
为满足勘查地球化学对化探数据处理越来越精细的要求,把人工神经网络和统计分析结合起来形成地球化学场精细结构解析方案。该方案包括对地球化学样品的分类和对各类样品性质的详细研究,目的在于提供便捷的数学和计算机软件工具,以提取化探数据中的深层信息。可以用于:①研究各组样品中元素含量水平和组合特征以解释可能的矿种;②研究元素组合特征与指示元素的关联和区别以揭示可能的成矿作用过程;③研究异常样品的空间组合属性以揭示地球化学场的精细结构;④研究异常样品之间的差异性以缩小找矿靶区;⑤综合分析以确定剥蚀深度和找矿前景。该方案也适用于环境地球化学及矿产资源预测研究。 相似文献
152.
The paper introduces the horizontal crustal movement obtained from GPS observations in the regional networks (including the
basic network and the fiducial network) of the Crustal Movement Observation Network of China (CMONOC) carried out in 1999
and 2001. This paper is characterized by the acquisition of the horizontal displacement velocities during the period from
1999 to 2001 at the observation stations in the regional networks with datum definition of a group of stable stations with
small mutual displacements in east China. Based on the most detailed map of horizontal crustal movement in Chinese mainland,
the division of blocks, their displacements and deformations are studied. An approach to analysis of the intensity of the
horizontal crustal deformation is proposed. The general characteristics of the recent horizontal crustal movement in Chinese
mainland and that before the Kunlunshan earthquake of M=8.1 on November 14, 2001 are analyzed.
Foundation item: The National Development and Programming Project for Key Basic Research (95-13-03-07). 相似文献
153.
神经网络在判别煤矿突水水源中的应用 总被引:6,自引:0,他引:6
矿井突水水源的识别是矿井防治水工作的基础,快速准确地判别突水的来源对整个矿井的安全生产起着十分重要的作用。以峰峰矿区梧桐庄矿为例,应用神经网络的方法,对矿井突水水源进行了系统研究。结果表明,运用该方法取得了较好的效果,并可以用此模型来解决类似的评价和判别问题。 相似文献
154.
155.
昌马水库右岸山体稳定性研究 总被引:2,自引:0,他引:2
昌马水库导流排砂洞塌方导致右岸山体发生松动 ,本文在大量地质资料的基础上 ,对右岸岩体裂隙网络进行模拟 ,同时 ,采用极限分析能量法和有限元数值模拟方法等对右岸山体的稳定性进行分析研究 ,并提出相应的加固方案。 相似文献
156.
Determination and application of the weights for landslide susceptibility mapping using an artificial neural network 总被引:38,自引:0,他引:38
The purpose of this study is the development, application, and assessment of probability and artificial neural network methods for assessing landslide susceptibility in a chosen study area. As the basic analysis tool, a Geographic Information System (GIS) was used for spatial data management and manipulation. Landslide locations and landslide-related factors such as slope, curvature, soil texture, soil drainage, effective thickness, wood type, and wood diameter were used for analyzing landslide susceptibility. A probability method was used for calculating the rating of the relative importance of each factor class to landslide occurrence. For calculating the weight of the relative importance of each factor to landslide occurrence, an artificial neural network method was developed. Using these methods, the landslide susceptibility index (LSI) was calculated using the rating and weight, and a landslide susceptibility map was produced using the index. The results of the landslide susceptibility analysis, with and without weights, were confirmed from comparison with the landslide location data. The comparison result with weighting was better than the results without weighting. The calculated weight and rating can be used to landslide susceptibility mapping. 相似文献
157.
James R Faulconbridge 《Area》2004,36(3):235-244
The launch of the Euro and the location of the European Central Bank in Frankfurt initially was seen as a threat to London's pre-eminent position in European financial geographies. This paper explains why in fact this was not the case. To do this, the paper is divided in two. Firstly, it reviews the literatures that help to explain financial geographies. It is argued that we need to move away from investigating attribute properties such as financial turnover and instead examine the role of networks and interdependencies in producing financial geographies. Secondly, it identifies London's dominance and Frankfurt's growth as a complementary centre through quantitative analysis and then explains how European networks and interdependencies produce this, based on insights from interviews with investment bankers and insurance institution workers in the two cities. 相似文献
158.
159.
以2000网为例,根据1991~2001年累积的GPS重复观测资料,利用GIPSY软件建立具有1115个测点的地壳运动模型。在此基础上,采用双三次样条函数数值拟合法,模拟出2000网网点相对西安基准站的地壳形变改正值,并给出了效果图。 相似文献
160.