顾及起始数据误差影响时单位权中误差的估值   总被引：1，自引：0，他引：1  

黄加纳 《武汉大学学报(信息科学版)》1986,(4)

本文推导了在附有条件的间接平差和附有未知数的条件平差两种方法中,顾及起始数据误差影响时,计算单位权中误差估值(?)的公式,并以两个实例说明,平差时应该考虑起始数据误差对(?)的影响。  相似文献   

浅层地温误读的分析与判断     

施淑嬿 《气象》1995,21(12):38-41

作者介绍了在多年地面信息资料处理中积累的关于浅层地温误读的分析与判断经验，总结出人机结合的５个分析判断方法，在工作中收到了良好效果，从而保证了信息资料和气表资料的准确性。  相似文献   

矿体储量及其计算参数的误差公式和金属储量误差的回归模型     

池顺都 《地球科学》1987,(6)

据个旧锡矿开发勘探资料,在计算机上实现不同网度稀空试验的结果、讨论了误差估计问题,提出了矿石品位、矿体厚度、矿体投影面积、矿体体积和金属储量等误差估值公式。以实例建立了不同穿透样锡品位变化系数值的金属储量误差与工程数量的回归模型,并将其应用于金属储量误差估计和工程效果的预测。  相似文献   

Digital modeling studies for evaluation of hydrogeological characteristics in Shadnagar granite basin,Andhra Pradesh,India     

B. H. Briz-Kishore 《Journal of Earth System Science》1982,91(3):219-234

The use of digital models has increased significantly in recent years with the accessibility of fast computing machines. A variable dimensioned digital model was constructed for the Shadnagar granite basin using SPECTRUM-7 micro computer to integrate various hydrogeological characteristics and for their quantitative evaluation. The basin has an areal extent of 437 sq km and is demarcated with clear water divides in all directions. Transmissivity, recharge and discharge at each cell of the basin area were estimated by trial and error simulation of the hydrogeological phenomenon under steady state condition. Dynamic simulation at representative nodes facilitated the estimation of storage coefficient. The capability of the constructed model was established by the conformance of the simulated hydrographs with the actual behaviour of the ground water system. The entire studies ammended the earlier arrived estimates of various input/output hydrogeological parameters and evolved a methodology for efficient processing of aquifer simulation data  相似文献   

Risk Management for Petroleum Reservoir Production: A Simulation-Based Study of Prediction     

James Glimm  Shuling Hou  Hongjoong Kim  Yoon-ha Lee  David H. Sharp  Kenny Ye  Qisu Zou 《Computational Geosciences》2001,5(3):173-197

We consider numerical solutions of the Darcy and Buckley–Leverett equations for flow in porous media. These solutions depend on a realization of a random field that describes the reservoir permeability. The main content of this paper is to formulate and analyze a probability model for the numerical coarse grid solution error. We explore the extent to which the coarse grid oil production rate is sufficient to predict future oil production rates. We find that very early oil production data is sufficient to reduce the prediction error in oil production by about 30%, relative to the prior probability prediction.  相似文献   

三角形量测法在隧道变形监测中的应用研究   总被引：3，自引：0，他引：3  

曾鼎华  张永兴  阴可  陈建功 《水文地质工程地质》2005,32(5):113-115

通过对隧道变形监测中三角形量测法原理、计算公式的分析,认为公式中的三角形三边长度并不是收敛计的读数,两者相差一个收敛计本身的附加长度,这是使监测数据产生误差的原因之一。同时探讨了忽略收敛计附加长度引起的误差对监测结果的影响,并结合工程实例介绍了在实测过程中应注意的问题及误差原因。  相似文献   

灰色GM(1,1)残差修正模型在滑坡预测中的对比应用   总被引：2，自引：0，他引：2  

李秀珍  孔纪名  王成华 《山地学报》2007,25(6):741-746

在传统GM(1,1)模型的基础上,经过不同方式的残差修正,分别建立了一阶残差修正GM(1,1)模型和二阶残差修正GM(1,1)模型。根据滑坡的监测资料,对变形曲线为光滑型滑坡(如黄龙西村滑坡、某滑坡)和阶跃型滑坡(如新滩滑坡、洒勒山新滑坡)分别建立了传统GM(1,1)模型和一阶、二阶残差修正模型,并对不同滑坡各模型的预测精度进行了分析比较。结果表明,残差修正GM(1,1)模型的预测精度明显高于传统GM(1,1)模型的预测精度。对变形曲线为光滑型的滑坡,二阶残差修正GM(1,1)模型的预测精度一般高于一阶残差修正GM(1,1)模型的预测精度;对变形曲线为阶跃型的滑坡,一阶残差修正GM(1,1)模型的预测精度高于二阶残差修正GM(1,1)模型的预测精度。  相似文献   

Confidence intervals for earthquake source parameters   总被引：2，自引：0，他引：2  

G. A. Prieto  D. J. Thomson  F. L. Vernon  P. M. Shearer  R. L. Parker 《Geophysical Journal International》2007,168(3):1227-1234

  相似文献   

Investigation of the Calibration Function of Local Earthquake Magnitude （ ML ） in the Fujian-Taiwan Region     

Lin Xiankan 《中国地震研究》2007,21(2):139-146

The author carefully selected earthquakes with M_L=4.0～5.0, 215 occurring in the crust in the Taiwan region. The attenuation characteristics of maximum displacement recorded by the Fujian digital network have been obtained by multi-analysis as follows:logA=2.07 231.1/Δ (150km≤Δ≤650km) And the corresponding expression of calibration function is, R(Δ)=3.45-231.1(1/Δ-0.01) (150km≤Δ≤650km) Then, the author determined the magnitude and its error with the data from the Fujian network using the calibration function brought forward in 1997 and the above formula for 790 earthquakes occurring in the crust in the Taiwan region from September 1997 ～ August 2005. The result indicates that the average error of the network is 0.20 with the former and 0.18 with the latter. The average error is 0.13 with the latter with station correction. Compared with the magnitude determined by Taiwan seismologists, the magnitude value with the former is lower by 0.50 on average and that with the latter is higher by 0.08 on average.  相似文献   

Towards error‐free hybrid simulation using mixed variables     

Tarek Elkhoraibi  Khalid M. Mosalam 《地震工程与结构动力学》2007,36(11):1497-1522

Two procedures are developed and implemented in a hybrid simulation system (HSS) with the aim of enhancing the accuracy and reliability of the online, i.e. pseudo‐dynamic, test results. The first procedure aims at correcting the experimental systematic error in executing the displacement command signal. The error is calculated as the difference between command and feedback signals and correlated to the actuator velocity using the least‐squares method. A feed‐forward error compensation scheme is devised leading to a more accurate execution of the test. The second procedure employs mixed variables with mode switching between displacement and force controls. The newly derived force control algorithm is evaluated using a parametric study to assess its stability and accuracy. The implementation of the mixed variables procedure is designed to adopt force control for high stiffness states of the structural response and displacement control otherwise, where the resolution of the involved instruments may favour this type of mixed control. A simple pseudo‐dynamic experiment of steel cantilever members is used to validate the HSS. Moreover, two experiments as application examples for the two developed procedures are presented. The two experiments focus on the seismic response of (a) timber shear walls and (b) reinforced concrete frames with and without unreinforced masonry infill wall. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献