排序方式: 共有102条查询结果,搜索用时 62 毫秒
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利用水深不确定度探测测深异常值的方法 总被引:1,自引:1,他引:0
利用最小二乘支持向量机(LS-SVM)合理地构造出海底趋势面关键在于训练样本的选取.在构造海底趋势面的过程中,提出并实现了一种基于不确定度优化训练样本的方法.为了检验该方法的有效性,选取实测的多波束测深数据进行验证,并与趋势面滤波法进行比较.结果表明,该方法能有效地抑制较大偏差训练样本的影响,构造的海底趋势面更为合理,... 相似文献
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利用线性最小方差估计方法,以正交投影理论为工具,推导了动态线性系统在状态噪声为有色噪声情形下的状态预测值及其相应的协方差阵.在形式上,此预测值比经典Kalman滤波预测值多出一项,该项包含了前一时刻的新息.对新预测值进行分析,得出了有色状态噪声条件下Kalman滤波的新算法,扩展了经典Kalman滤波的应用范围.最后通... 相似文献
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RESEARCH ON GENESIS OF M4.2 AND M4.5 EARTHQUAKE SEQUENCES IN MARCH 2014 IN ZIGUI COUNTY,HUBEI PROVINCE
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On 27th and 30th March 2014, an M4.2 and M4.5 earthquake sequence occurred in Zigui County, Hubei Province, and the earthquake sequence type is double seismic type. The two earthquake sequences occurred at the water unloading stage of the 175m trial impounding, and G-R relations showed the similar characteristics with that of the tectonic earthquakes. In order to verify the influences of dam reservoir on earthquake triggering, ETAS model was introduced, the results showed that the slow water level changes had little impact on the occurrence of earthquake. Double difference precision relocation results indicated that the two earthquake sequences occurred at the intersection part of a NE-striking fault and the NNW-striking Xiannvshan Fault, and the preferred direction of aftershock distribution was separately NE and NNW. Moment tensor inversion method and P wave initial motion method were used to determine the focal mechanisms of the two earthquakes, and the results indicated that the two earthquakes were controlled by the regional tectonic stress field and were of reverse-slip type. Comprehensive analysis showed that the M4.2 earthquake was caused by a small-scale fault striking NE with a big dip angle. From the hypocenter profile, it can be seen that the M4.2 earthquake sequence was restrained by an east-dip fault, and the M4.5 earthquake sequence was the product under the conjugate action of the NE-striking fault and the NNW-striking Xiannvshan fault. 相似文献
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新疆阿尔泰南缘克因布拉克铜锌矿区黑云母二长花岗岩地球化学特征及意义 总被引:1,自引:0,他引:1
新疆阿尔泰南缘克因布拉克铜锌矿区出露大面积花岗岩,岩性主要为二长花岗岩、钾长花岗岩、黑云母花岗岩和英云闪长岩,矿体赋存于二长花岗岩与上志留统-下泥盆统康布铁堡组外接触带中。室内显微镜下鉴定二长花岗岩发育二云母二长花岗岩和黑云母二长花岗岩2种岩相。黑云母二长花岗岩具有高硅、高碱、贫钠富钾、准铝质-过铝质的特点;微量元素特征表现为Rb、Th、K、Ce、Nd、Tb富集,Ba、Nb、Sr、Ti强烈亏损;稀土元素配分模式为轻稀土相对富集的右倾型,具有稀土总量中等及中等负铕异常的特点。这些特征表明该花岗岩属于高钾钙碱性准铝质-过铝质S型。岩石的ISr(t)值为0.703 039~0.705 729,εNd(t)值相对较低,多数为近于0的负值,T2DM两阶段模式年龄集中在1.145~1.194 Ga。岩石可能由中元古界富含黑云母的变质砂岩或正变质岩和少量幔源物质在较低压力条件下熔融形成,源区有斜长石的残留。地球化学特征表明该区花岗岩具有良好的含矿性,其矿床形成于后碰撞的伸展环境,成矿作用与二长花岗岩的岩浆期后热液有关。 相似文献
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介绍了利用GPS掩星反演地球中性大气参数的原理.在实际解算中,总结出用迭代法解多普勒观测方程、数值积分法求大气折射指数、用最小二乘法模拟大气折射指数与高度的函数关系.对特定掩星事件的数据进行了反演计算,并对计算结果进行了分析. 相似文献
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介绍了GPS遥感大气水汽含量技术的类型、实时GPS遥感水汽技术的研究现状以及地基GPS大气探测的基本原理。提出了用非差精密单点定位模式进行实时GPS遥感水汽探测的基本构想和需要解决的关键问题,并对非差精密单点定位的主要误差源进行了简要分析和评述。 相似文献
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我国岩溶塌陷研究综述 总被引:19,自引:0,他引:19
随经济的不断发展,对岩溶区资源的开发日益增强,由此引发的岩溶塌陷问题也日趋频繁、严重,已成为岩溶区可持续发展的一大障碍,有效减轻其造成的危害势在必行。文章根据近年来国内外岩溶塌陷的研究现状及发展,概述了岩溶塌陷的三大形成条件:一定发育程度的岩溶、上覆盖层、岩溶地下水系统;以及中国岩溶塌陷的时空分布规律,分别举例例证了它的几种成因机制,如重力致塌、潜蚀致塌等。由于其突发性及危害性,有必要对岩溶塌陷的预测防治进行深入研究,做到防灾减灾。基于此,总结了中国岩溶塌陷的监测预报和安全评价等方面的新方法和措施等。针对塌陷的形成条件、塌陷现象或其危情的存在状况及其危害性,归纳了有针对性的防治措施。 相似文献