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91.
论多种数据联合反演的模式及算法 总被引:9,自引:3,他引:6
针对日益丰富的数据资料,综述了大地测量反演的发展进程,论述了多种数据联合反演的意义和必要性,给出了兼顾权比确定的大地测量、地震和地质三类数据的联合反演模式及采用水准测量、GPS和重力三种数据联合反演断层参数的具体公式,特别介绍了求解优化问题所有全局最优解的区间算法,并给出了基本算例,结果体现了区间算法无可比拟的优越性及其在大地测量反演领域中的应用前景。 相似文献
92.
本文主要介绍沙赫(Shan,P.M.)公式,对二维任意倾斜地层的层速度计算的应用效果。依据实际地层剖面Φ、V、Z参数的可能变化,设计18个较为复杂的地层模型进行了大量试算,并与Dix公式计算结果作了对比,表明对任意倾斜地层应采用沙赫公式提取层速度才是适宜的。 相似文献
93.
Optimum design of nailed soil slopes 总被引:12,自引:0,他引:12
In this paper, a generalized method of computer based optimum design of soil-nailed slopes is reported. A limit equilibrium formulation satisfying overall and internal equilibrium and considering the effect of tensile resistance of the reinforcement has been used in computing the stability of nailed slopes. The quantity of steel requirement for raising the factor of safety to a desired value is estimated. The location, size (length and diameter) and orientation of the nails and the location and shape of the critical shear surface have been treated as variables. The solutions have been isolated by formulating the problem as one of non-linear programming. The applicability of the developed method has been verified by comparing the predicted failure surfaces with those observed in model tests as well as in the field and also reported theoretical results. 相似文献
94.
Average slip rate,earthquake rupturing segmentation and recurrence behavior on the Litang fault zone,western Sichuan Province,China 总被引:3,自引:0,他引:3
XU Xiwei WEN Xueze YU Guihua ZHENG Rongzhang LUO Haiyuan & ZHENG Bin . Institute of Geology China Earthquake Administration Beijing China . Earthquake Administration of Sichuan Province Chengdu China 《中国科学D辑(英文版)》2005,48(8):1183-1196
The Litang fault zone (LFZ) is an important active fault within the northwestern Sichuan sub-block. To-gether with the Garzê-Yushu, Xianshuihe, and An-ninghe fault zones on its northern, eastern and south-eastern sides, the LFZ constitutes the lateral extrusion tectonic system in the southeastern part of the Qing-hai-Tibetan Plateau[1,2] (Fig. 1). According to instru-mental records, historical recordings and field investi- gation, an earthquake (Ms7.3) occurred on its middle to south se… 相似文献
95.
LIU Feng HU Fei & ZHU Jiang . College of Environmental Sciences Peking University Beijing China . LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2005,48(8):1270-1279
The deterioration of air quality is threatening the life and health of people. Scientists in China and other countries have done a great deal of research work on the details of air pollution and the methods of preven-tion and control during the past decades. Up to now, most of the achievements are concentrated on the techniques of controlling pollutant sources and the programs of reduction, which focus on the improve-ment of air quality and the restoration of environment. The techniques of con… 相似文献
96.
97.
Groundwater models need to account for detailed but generally unknown spatial variability (heterogeneity) of the hydrogeologic model inputs. To address this problem we replace the large, m-dimensional stochastic vector β that reflects both small and large scales of heterogeneity in the inputs by a lumped or smoothed m-dimensional approximation γθ∗, where γ is an interpolation matrix and θ∗ is a stochastic vector of parameters. Vector θ∗ has small enough dimension to allow its estimation with the available data. The consequence of the replacement is that model function f(γθ∗) written in terms of the approximate inputs is in error with respect to the same model function written in terms of β, f(β), which is assumed to be nearly exact. The difference f(β) − f(γθ∗), termed model error, is spatially correlated, generates prediction biases, and causes standard confidence and prediction intervals to be too small. Model error is accounted for in the weighted nonlinear regression methodology developed to estimate θ∗ and assess model uncertainties by incorporating the second-moment matrix of the model errors into the weight matrix. Techniques developed by statisticians to analyze classical nonlinear regression methods are extended to analyze the revised method. The analysis develops analytical expressions for bias terms reflecting the interaction of model nonlinearity and model error, for correction factors needed to adjust the sizes of confidence and prediction intervals for this interaction, and for correction factors needed to adjust the sizes of confidence and prediction intervals for possible use of a diagonal weight matrix in place of the correct one. If terms expressing the degree of intrinsic nonlinearity for f(β) and f(γθ∗) are small, then most of the biases are small and the correction factors are reduced in magnitude. Biases, correction factors, and confidence and prediction intervals were obtained for a test problem for which model error is large to test robustness of the methodology. Numerical results conform with the theoretical analysis. 相似文献
98.
周跳的探测与修复是GPS载波相位数据处理中一项重要的任务。首先介绍了双频相位求差法探测与修复周跳的原理;其次,利用Fortran语言编制了相应的程序,并通过实例分析了在不同采样率下探测周跳与修复的效果;最后讨论了该方法探测周跳的不足。 相似文献
99.
本研究提出了一种在边界层风廓线雷达连续运行的降水探测时段中对降水频谱进行在线分析的新的应用方式。详细介绍了边界层风廓线雷达在线分析原理和方法。同时结合典型降水频谱个例,分析了可获得的多个潜在的气象参数和信息。并指出,该在线分析方式的实施可以使风廓线雷达的应用领域从晴空探测向降水测量拓展;有效缓解当前风廓线雷达应用存在的瓶颈问题;间接证明边界层风廓线雷达组网间距不固定的观点。文章分析说明,随着在线分析方式的推广应用,边界层风廓线雷达将成为单站精细化气象探测和预报/服务的重要工具。 相似文献
100.