The Double Column Block Method,an Effective Solution for Large sparse symmetric System of Linear Equations

The double Column block method applies to solute of large sparse linear simultaneous equations in finite element analysis. At present the portioned triangular decomposition method is generally used for solving large systems of linear equations in FE. With the partition of the coefficient matrix dependent on its bandwidth, the solution of problems with a large bandwidth is restricted owing to the computer core storage and hence it is difficult for this method to solve some large-scal FE problems, especially the three-dimensional problems. This difficulty has been overcome by the double column block method, completely independent of the bandwidth, by means of our method the coefficient matrix is partitioned according to computer core storage capacity. It is proved that this approach is successful and effective. Based on this method, the solution has been completed of the three-dimensional FE problem with 124 twenty-node and 8 sixteen-node isoparametric elements, and 831 nodes, having a maximum half-bandwidth of 1746 and global stiffness matrix storage of more than 5000 K bytes. The computation was performed on PE-3220 minicomputer and only a core storage of 685 K bytes was used. The double column block method makes it possible for minicomputer and high-level microcomputer to be applied to calculations in large-scale FE problems.     

A Projection Method for Solving Systems of Linear Equations: Gravimetry Applications

Doklady Earth Sciences - Existing methods for solving inverse problems, such as the regularization method, look mostly for a quasi-solution that may not be a solution to the original problem, but...     

对角元有非负增量的对称正定方程组的ICCG算法

根据对角元有非负增量的对称正定方程组的特征，结合不完全Cholesky共轭梯度法，给出了求解线性方程组一种有效算法。     

大区域非规则采样系统ETo的最优等值线图Kriging法绘制及应用

作物需水量是水资源循环与水分消耗的主要形式,也是资源分配与评价的主要依据.参考作物需水量(ETo)是其中的一个核心部分.目前国内外研究仅关注ETo计算方法及等值线图绘制,并多以传统的线性插值方法进行手工绘制或计算机绘制.而关于大区域非规则采样ETo最优等值线图绘制方法尚少见报道.ETo主要受区域性蒸发面的液体扩散及其向上空的气体紊流的空气动力学作用即环境条件影响,主要与气象和地理条件有关,具有区域性变量的特征.本研究以内蒙古自治区复杂气候条件和地理环境下绘制牧草ETo区域性空间变异规律和最优等值线图为目标,采用了地质统计学方法并探讨Kriging最优无偏估计方法用于大区域非规则采样条件下区域信息估计的途径.根据118万km2面积内135个非规则分布气象站30年气象资料,通过对非规则采样信息的正则化处理,在传统最优内插估计方法基础上,进行了误差控制下的适当外推,构成了内插与外推的合理结合.在提供资源估值的同时还可提供估值误差б2k.对大区域非规则网格等值线图绘制提供了科学有效的方法.     

大口径钻头设计与合理使用专家系统

三口径钻头设计与合理使用专家系统,由大口径钻头设计专家系统、大口径钻头合理使用专家系统、大口径电脑图库三部分组成。详细介绍了该专家系统的知识体系、知识表示以及知识库的维护等内容。     

用ArcIMS建立震源机制解数据发布系统方法浅析

随着WebGIS(网络地理信息系统)应用的不断深入,我们将WebGIS技术引入到震源机制解数据分析,通过将数据库信息与地理空间属性信息相结合,实现了数据库信息图形化,统计分析自动化,数据访问和查询网络化。本文通过介绍用ArcI MS3.1建立震源机制解数据发布系统,论述了ArcI MS体系结构,详述了中国及邻区地震震源机制解数据发布系统的总体结构和用ArcI MS建立震源机制解数据发布系统的方法,并就系统开发中的技术要点进行了论述。     

饱水白云岩临界点、骨架和流体弹性参数的数值计算

基于临界孔隙度模型,提出了用岩石的整体弹性信息反演求取临界点、流体和骨架等局部弹性参数的数值计算方法和双向线性回归计算公式;结合饱水白云岩的样品测试数据,以孔隙度为自变量和因变量,对密度和密度与纵、横波速度平方的乘积分别进行了数值计算。以测试样品的整体信息求得其临界点、流体和骨架弹性参数值,并与实测数据做了相关性分析,其相关系数高达90%,充分表明数值计算公式的正确性和实现方法的有效性。岩石骨架、流体弹性参数的数值反演计算在油气勘探领域中具有巨大潜力,运用测井曲线和地震数据,可以反演求出岩石孔隙中流体弹性参数(密度、速度),对直接指示油层、气层起到重要作用。     

The Use of Remote Sensing Data for Probabilistic Assessment of an Impact on a Linear Structure

Doklady Earth Sciences - This study is aimed at developing a remote sensing technique for assessing the probability of an impact on linear engineering structures by the example of lateral river...     

大港油田埕海二区沙一下碳酸盐岩储层测井评价方法

大港油田埕海二区下第三系沙河街组储层为一套微裂缝发育的低孔低渗复杂储层,其岩性包括白云岩、白云质灰岩、油页岩等.运用常规测井解释方法不能准确反映该储层的物性特征,通过地质、岩心、测井、地震等资料,对该区各类复杂储层进行了分析研究,在储层定性解释和定量评价的基础上建立了测井解释模型.该模型应用于研究区多口井,取得了较好的...     

The crustal continuum model for late-Archaean lode-gold deposits of the Yilgarn Block,Western Australia

Most Archaean gold ores belong to a coherent genetic group of structurally controlled lode-deposits that are characteristically enriched in Au with variable enrichments in Ag, As, W, Sb, Bi, Te, B and Pb, but rarely Cu or Zn, and are surrounded by wallrock alteration haloes enriched in K, LILE and CO₂, with variable Na and/or Ca addition. Evidence from the Yilgarn Block of Western Australia, combined with similar evidence from Canada and elsewhere, indicates that such deposits represent a crustal continuum that formed under a variety of crustal régimes over at least a 15 km crustal profile at PT conditions ranging from 180°C at <1 kb to 700°C at 5 kb. Individual deposits, separated by tens to hundreds of kilometres, collectively show transitional variations in structural style of mineralisation, vein textures, and mineralogy of wallrock alteration that relate to the PT conditions of their formation at varying crustal depths. Specific transitions within the total spectrum may be shown also by deposits within gold camps, although nowhere is the entire continuum of deposits recorded from a single gold camp or even greenstone belt. Recognition of the crustal continuum of deposits implicates the existence of giant late-Archaean hydrothermal systems with a deep source for the primary ore fluid. A number of deep fluid and solute reservoirs are possible, including the basal segments of greenstone belts, deep-level intrusive granitoids, mid-to lower-crustal granitoidgneisses, mantle lithosphere, or even subducted oceanic lithosphere, given the probable convergent-margin setting of the host greenstone terranes. Individual stable and radiogenic isotope ratios of fluid and solute components implicate fluid evolution from, or equilibrium with, a number of these reservoirs, stressing the potential complexity of pathways for fluid advection to depositional sites. Lead and strontium isotope ratios of ore-associated minerals provide the most persuasive evidence for fluid advection through deep-level intrusive granitoids or granitoid-gneiss crust, whereas preliminary oxygen isotope data show that mixing of deeply sourced fluid and surface waters only occurred at the highest crustal levels recorded by the lode gold deposits.