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111.
通过引人泊松括号,分析了无限维Hamilton的性质,并将其推广到广义Hamilton系统,且从理论和实用角度讨论了这类广义Hamilton系统的辛格式构造问题,从而为辛几何算法在一般的时间发展方程的数值求解提供新的具体途径。 相似文献
112.
A new probabilistic analytical approach to evaluate seismic system reliability of large lifeline systems is presented in this paper. The algorithm takes the shortest path from the source to the terminal of a node weight or edge weight network as decomposition policy, using the Boolean laws of set operation and probabilistic operation principal, a recursive decomposition process then could be constructed. For a general weight network, the modified Torrieri method (NTR/T method) is introduced to combine with the suggested algorithm. Therefore, the recursive decomposition algorithm may be applied to evaluate the seismic reliability of general lifeline systems. A series of case studies, including a practical district electric power network system and a large urban water supply system, show that the suggested algorithm supplies a useful probabilistic analysis means for the seismic reliability evaluation of large lifeline systems. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
113.
应用CP网络进行岩性识别 总被引:2,自引:3,他引:2
为通过测井解决岩性识别问题,引入了具有分类准确、算法简练等优点的CP(Counter-Propagation)网络。在详细介绍CP网络的网络模型和算法的基础上,结合某油田的实际测井资料,进行了CP网络识别研究。应用结果表明:CP网络训练周期短、识别准确率高、不存在收敛问题。通过试验研究得出结论:CP网络完全可以用于解决岩性识别等问题,具有广阔的应用前景。 相似文献
114.
遗传算法在边坡数值计算中的应用 总被引:4,自引:0,他引:4
改进了进化方向的遗传算法与有限元数值法,结合并研制了相应的软件。应用该软件对多类型岩土边坡进行弹性模量、内聚力、内摩擦角等参数反演分析,显示误差很小,收敛速度也很快,这说明改进进化方向遗传算法这种新型的优化算法在多类型岩土参数优化估计中具有独特的优势。 相似文献
115.
116.
Introduction For the seismic design of special structures such as nuclear power station, marine platform, long-span bridge and dam, generally the time-history response analysis of the structure under seismic excitation is imperative, which was coded in most seismic design codes. The earthquake records suitable for the seismic situation and site condition are necessary to be used as the seismic input in the dynamic analysis of structures. As a result of the limited observational condition of st… 相似文献
117.
边银菊 《地震学报(英文版)》2002,15(5):540-549
Introduction Artificial Neural Network (ANN) is an important branch of artificial intelligence. It is proposed on the foundation of the study on modern neural science, is a man-made network that can implement some functions based on the mans comprehensive understanding for cerebral neural network (HAN, WANG, 1997). ANN is a mathematical model of simplified human brain neural network and is used to simulate the structures and functions of human brain neural network. ANN is a complex netw… 相似文献
118.
Chad Trabant Clifford Thurber William Leith 《Physics of the Earth and Planetary Interiors》2002,131(2):155-171
We utilized nuclear explosions from the Degelen Mountain sub-region of the Semipalatinsk Test Site (STS), Kazakhstan, to assess seismic location capability directly. Excellent ground truth information for these events was either known or was estimated from maps of the Degelen Mountain adit complex. Origin times were refined for events for which absolute origin time information was unknown using catalog arrival times, our ground truth location estimates, and a time baseline provided by fixing known origin times during a joint hypocenter determination (JHD). Precise arrival time picks were determined using a waveform cross-correlation process applied to the available digital data. These data were used in a JHD analysis. We found that very accurate locations were possible when high precision, waveform cross-correlation arrival times were combined with JHD. Relocation with our full digital data set resulted in a mean mislocation of 2 km and a mean 95% confidence ellipse (CE) area of 6.6 km2 (90% CE: 5.1 km2), however, only 5 of the 18 computed error ellipses actually covered the associated ground truth location estimate. To test a more realistic nuclear test monitoring scenario, we applied our JHD analysis to a set of seven events (one fixed) using data only from seismic stations within 40° epicentral distance. Relocation with these data resulted in a mean mislocation of 7.4 km, with four of the 95% error ellipses covering less than 570 km2 (90% CE: 438 km2), and the other two covering 1730 and 8869 km2 (90% CE: 1331 and 6822 km2). Location uncertainties calculated using JHD often underestimated the true error, but a circular region with a radius equal to the mislocation covered less than 1000 km2 for all events having more than three observations. 相似文献
119.
利用OLE自动化方法,将MapInfo集成在VB中,在手工地震交切定位的基础上,开发了计算机定位程序,该程序与传统的定位方法相比,精度和效率都有较大幅度的提高。并在地震应急中发挥了作用。 相似文献
120.
针对三维地震数据插值,提出采用Laplacian算子进行光滑约束的插值方法,并借鉴Mallet研究的离散光滑插值思路,采用预条件共轭梯度法,直接生成网格节点上的值,从而回避寻求满足插值方程的函数. 为了实现其中Laplacian算子的快速求逆,文中引入Claerbout螺旋坐标系谱因式分解理论. 在螺旋坐标系下,Laplacian算子的表示矩阵具有Toeplitz结构,其快速求逆可由谱法LU分解实现. 基于二维离散光滑插值,文中还给出共轭梯度法与NMO相结合的沿时间切片逐层处理的离散光滑插值流程. 最后,应用该方法对模型数据和实际三维地震数据进行了处理. 相似文献