Reservoir Characterization of McMurray Formation by 2D Geostatistical Modeling

There is a need to estimate reserve uncertainty for large lease areas. Detailed 3D models of heterogeneity are not necessarily required, but there is a need to integrate all available data into an in-situ reserve estimate with uncertainty. A 2D mapping approach is presented to appraise reserves accounting for multiple variables, multiple data sources, and uncertainty. The approach can be considered in three primary steps: (1) Bayesian updating is used to determine local distributions of uncertainty for each primary variable while integrating multiple secondary information, (2) matrix simulation is employed to jointly and simultaneously simulate multiple collocated variables to determine a derived variable such as OOIP, and (3) probability field simulation then is applied to permit joint simulation of multiple locations. This methodology permits local and global uncertainty assessment while integrating multiple sources of information. An application to the McMurray Formation in Alberta, Canada is demonstrated.     

Updating and computing the geoid using two dimensional fast Hartley transform and fast T transform

In the analyses of 2D real arrays, fast Hartley (FHT), fast T (FTT) and real-valued fast Fourier transforms are generally preferred in lieu of a complex fast Fourier transform due to the advantages of the former with respect to disk storage and computation time. Although the FHT and the FTT in one dimension are identical, they are different in two or more dimensions. Therefore, first, definitions and some properties of both transforms and the related 2D FHT and FTT algorithms are stated. After reviewing the 2D FHT and FTT solutions of Stokes' formula in planar approximation, 2D FHT and FTT methods are developed for geoid updating to incorporate additional gravity anomalies. The methods are applied for a test area which includes a 64×64 grid of 3^′×3^′ point gravity anomalies and geoid heights calculated from point masses. The geoids computed by 2D FHT and FTT are found to be identical. However, the RMS value of the differences between the computed and test geoid is ±15 mm. The numerical simulations indicate that the new methods of geoid updating are practical and accurate with considerable savings on storage requirements. Received: 15 February 1996; Accepted: 22 January 1997     

3S技术在数据库数据更新中的应用

主要介绍了“3S”技术及其在数据库数据更新方面发展的状况，并以1：250000数据库更新为例，简述了利用“3S”技术进行数据库数据更新的基本过程及步骤。     

1：25万地图数据库更新中遥感影像的处理方法

卫星遥感影像已成为快速补充与更新地理信息的主要方法，以对1：25万地图数据库的更新为例，研究遥感影像选择预处理与变换定位的方法。     

独立分量分析及其在地震信息处理中应用初探

独立分量分析(ICA)是最近才发展起来的一种统计学方法，旨在寻求对非高斯分布数据进行有效表示，使得各个分量在统计学上独立，或者尽最大可能地独立。许多应用中，这种表示意在获取数据的基本结构，包括特征提取和信号分离。本文给出ICA的基本理论和快速算法，并对FastICA稍作改进，在分析地震信号特点的基础上，对其在地震信息处理中应用进行初步探索，表明ICA在地震信号处理中具有应用前景。     

大跨桥梁结构损伤诊断与安全评估的多尺度有限元模拟研究

探讨了以结构损伤诊断与安全评估为目标的大跨桥梁结构多尺度有限元模拟的策略与方案。在有限元模型误差来源分析的基础上,提出了大跨桥梁结构模型误差的分层次修正方法。通过对润扬长江大桥斜拉桥的有限元建模和模型修正过程,提出了大跨斜拉桥结构以损伤诊断与安全评估为目标的多尺度有限元模拟方法。研究表明,大跨桥梁结构的多尺度有限元模拟必须建立在模型误差分析的基础上,并采用模型误差的分层次修正方法才能较好的满足多尺度有限元模拟的技术要求。     

Online numerical simulation: A hybrid simulation method for incomplete boundary conditions

Hybrid simulation is a powerful and cost‐effective simulation technique to evaluate structural dynamic performance. However, it is sometimes rather difficult to guarantee all the boundaries on the physical substructures, especially when the boundary conditions are very complex, due to limited laboratory resources. Lacking of boundary conditions is bound to change the stress state of the structure and eventually result in an inaccurate evaluation of structural performance. A model updating‐based online numerical simulation method is proposed in this paper to tackle the problem of incomplete boundary conditions. In the proposed method, 2 sets of finite element models with the same constitutive model are set up for the overall analysis of the whole structure and the constitutive model parameter estimation of the physical substructure, respectively. The boundary conditions are naturally satisfied because the response is calculated from the overall structural model, and the accuracy is improved as the material constitutive parameters are updated. The effectiveness of the proposed method is validated via numerical simulations and actual hybrid tests on a RC frame structure, and the results show that the negative effect of incomplete boundary conditions is almost eliminated and the accuracy of hybrid simulation is very much improved.     

基于洪水预报系统误差反演的多河段联合校正方法

提出一种基于洪水预报误差系统反演的多河段联合校正方法.采用马斯京根法矩阵方程描述多河段多区间入流的河道汇流过程,基于动力系统反演理论建立洪水预报误差的递推方程,最后利用修正后的多河段状态变量经演算得到预报断面的洪水过程,进而达到多河段联合校正目的.对大渡河上游的应用示例结果表明：多河段联合校正方法考虑了河系中断面间的水力联系及预报误差在时程上的传递规律,可充分利用上游多断面实测和校正信息进行下游预报断面的误差修正,因此具有更高的校正精度和稳定性.     

Model-data fusion for seismic performance evaluation of an instrumented highway bridge

The paper presents a computationally efficient algorithm to integrate a probabilistic, non-Gaussian parameter estimation approach for nonlinear finite element models with the performance-based earthquake engineering (PBEE) framework for accurate performance evaluations of instrumented civil infrastructures. The algorithm first utilizes a minimum variance framework to fuse predictions from a numerical model of a civil infrastructure with its measured behavior during a past earthquake to update the parameters of the numerical model that is, then, used for performance prediction of the civil infrastructure during future earthquakes. A nonproduct quadrature rule, based on the conjugate unscented transformation, forms an enabling tool to drive the computationally efficient model prediction, model-data fusion, and performance evaluation. The algorithm is illustrated and validated on Meloland Road overpass, a heavily instrumented highway bridge in El Centro, CA, which experienced three moderate earthquake events in the past. The benefits of integrating measurement data into the PBEE framework are highlighted by comparing damage fragilities of and annual probabilities of damages to the bridge estimated using the presented algorithm with that estimated using the conventional PBEE approach.