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101.
地震和测井资料联合反演储层物性参数的方法   总被引:2,自引:0,他引:2  
为了充分利用测井资料较高的纵向分辨率及其反映井壁周围物性直接准确的特点和地震资料良好的横向可追踪性,针对厚储层和薄储层地震—地质模型分别提出了利用测井和地震资料联合反演纵横波速度和密度参数的方法。理论模型的计算结果表明,反演方法是切实可行的  相似文献   
102.
A bivariate meta-Gaussian density for use in hydrology   总被引:3,自引:0,他引:3  
Convenient bivariate densities found in the literature are often unsuitable for modeling hydrologic variates. They either constrain the range of association between variates, or fix the form of the marginal distributions. The bivariate meta-Gaussian density is constructed by embedding the normal quantile transform of each variate into the Gaussian law. The density can represent a full range of association between variates and admits arbitrarily specified marginal distributions. Modeling and estimation can be decomposed into i) independent analyses of the marginal distributions, and ii) investigation of the dependence structure. Both statistical and judgmental estimation procedures are possible. Some comparisons to recent applications of bivariate densities in the hydrologic literature motivate and illustrate the model.  相似文献   
103.
利用Cole-Cole模型组合和稀释系数理论,可以描述测量得到的视复电阻率频谱与地下多个电性体SIP真参数之间的正演关系。本利用此正演关系进行反演试算,并比较了几种Cole-Cole模型反演方案的效果;提出固定极化目标体和围岩体的极化率同时反演其它各SIP真参数的反演方案。结果表明在固定极化率为真值时,利用此反演方案可以稳定、准确、快速地得出地下电性体SIP真参数。  相似文献   
104.
For the problem of in-flight test site radiometric calibration for the FY-1D Meteorological Satellite onboard sensor's visible and near infrared channels,this paper described the calibration method,satellite-ground synchronous observation data acquired at China Dunhuang Calibration Test Site,parameter derivation and radiative transfer computation during the calibration,and the calibration result analysis.At FY-1D seven channels (with central wavelength at Channels 1:630 nm,2:865 nm;6:1610 nm;7:455 nm,8:505 nm;9:555 nm;10:932 nm),calibration coefficients obtained during the ground site calibration were compared with that respectively of prelaunch calibration.It is demonstrated that results of FY-1D onboard two sensors' (A and B) at channels 1,2,6 and 10 were close to pre-calibration,and the absolute difference of Gobi desert reflectance computed using test site and pre-launch calibration coefficients was no more than 2%. At other channels,large pre-launch calibration errors resulted in a poor consistency between the test site and pre-launch calibration.The errors can be corrected by the test site calibration results. Based on a rough estimation,the overall error of the calibration was about 6%. The paper also presented the in-flight vicarious calibration at the visible and near infrared channels of FY-1C sensor A which was launched in 1999 and has been put into operational mode since 2002.The results exhibit that FY-1C sensor's response has 23% attenuation at Channels 7 and 8,while only minor degradation at the other channels was found. During the mission,calibrations were also conducted at NOAA-17's Channels 1 and 2 (1:430-830 nm,2:500-1072 nm).A very good consistency has been achieved between the test site and pre-launched calibration results.  相似文献   
105.
The data, measured by a three-wavelength Integrating Nephelometer over Lanzhou City during the winters of 2001/2002 and 2002/2003 respectively, have been analyzed for investigating the scattering properties of atmospheric aerosols and exploring their relationship and the status of air pollution. The aerosol particle volume distribution is inverted with the measured spectral scattering coefficients. The results show that the daily variation of the aerosol scattering coefficients is in a tri-peak shape. The average ratio of backscattering coefficient to total scattering coefficient at 550 nm is 0.158; there exists an excellent correlation between the scattering coefficients and the concentration of PM10. The average ratio of the concentration of PM10 to the scattering coefficients is 0.37 g m-2, which is contingent on the optical parameters of aerosol particles such as the size distribution, etc.; an algorithm is developed for inverting the volume distribution of aerosol particles by using the histogram and Monte-Carlo techniques, and the test results show that the inversion is reasonable.  相似文献   
106.
采用文献[1]提出的技术模型,研制了云宵县5月暴雨预报方法,建立了4个因子结构简单而天气学意义明了的客观预报模型。经2000~2003年试用,这种基于场量因子的预报模型,未漏报,严格评定的准确率为67%,明显优于主观预报。  相似文献   
107.
Introduction In AD 1303, the great Hongtong, Shanxi, earthquake of magnitude 8 caused a very serious disaster, which killed over one hundred thousands people at least (Department of Earthquake Dis- *aster Prevention, State Seismological Bureau, 1995). On the occasion of commemorating this ca-tastrophe having occurred for 700 years, we have important problems that need to be answered: How long the average recurrence interval of the grea…  相似文献   
108.
After the 1995 Kobe earthquake, the expressway structures in Japan were retrofitted and they will not now be seriously damaged under a certain level of strong earthquake motion. However, the stability of a moving vehicle has not been investigated yet. It has been reported that drivers feel seismically induced vibrations, especially in the transverse direction of vehicles. Owing to this phenomenon, drivers have some difficulty in controlling the vehicles during strong shaking. For further safety promotion of the expressway networks, it is important to understand the drivers' reactions to seismic motion. The present authors have performed a series of seismic response analyses of a moving vehicle to investigate its response characteristics based on numerical simulation. However, the responses of the driver were not considered in the simulation process. In order to investigate the drivers' reactions during an earthquake, a series of virtual tests were conducted using a driving simulator. This driving simulator has six servomotor‐powered electric actuators that control its motions. Several types of tests were carried out for different examinees to investigate drivers' responses while controlling the simulator under seismic motion. The results of this study showed that a larger response time lag to strong shaking and over turning of the steering wheel may shift the vehicle into the next lane. According to this finding, trafficaccidents could possibly occur under strong ground shaking in the case of heavy traffic. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
109.
Based on Biot's wave equation, dynamic response of a circular tunnel with partially sealed liner in viscoelastic saturated soil is investigated. By introducing two scalar potential functions, the analytical solutions of stresses, displacements and pore pressure induced by axisymmetric gradually applied step load are derived in Laplace transform domain. Numerical results are obtained by inverting Laplace transform presented by Durbin and used to analyze the influences of partial permeable property of boundary and viscoelastic damping coefficient of soil on dynamic response of the tunnel. It is shown that the attenuation of radial displacement appeared with the increase of viscoelastic damping coefficient of soil, and relative rigidity of liner and soil, and the influence of partial sealing property of boundary on stresses, displacements and pore pressure is remarkable. The available solutions of permeable and impermeable boundary conditions are only two extreme cases of this paper.  相似文献   
110.
钱家店铀矿床U-Ra平衡系数特征研究   总被引:1,自引:0,他引:1  
本文探讨了可地浸砂岩型铀矿U-Ra平衡系数的计算方法,研究了钱家店砂岩型铀矿床U-Ra平衡系数的变化特征。这些成果为钱家店铀矿床放射性测井数据的修正、矿体边界的确定、铀矿资源量的计算提供了科学依据。  相似文献   
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