基础地理数据在智慧城市建设中的分析与应用     

焦煦  朱文英  黄瑞峰 《国土资源信息化》2012,(2):55-61

本文立足于研究基础地理数据在智慧城市建设中的重要性,提高智慧城市对基础地理数据应用水平,全面和深度应用基础地理数据推动经济社会率先转型升级,是建设智慧城市的内在要求。通过对基础地理数据组成和应用模式分析满足智慧城市中政府部门、企业单位和社会公众应用的需求。同时建立统一的标准规范、统一的数据管理、统一的运维机制保障智慧城市长效运行。  相似文献   

Petrology of phlogopite-sapphirine-bearing Al-Mg granulites from Ihouhaouene, In Ouzzal, Hoggar, Algeria: an example of phlogopite stability at high temperature   总被引：1，自引：0，他引：1  

H. MOURI  M. GUIRAUD  B. J. HENSEN 《Journal of Metamorphic Geology》1996,14(6):725-738

Al-Mg granulites, with cordierite, garnet, sapphirine, orthopyroxene, sillimanite, spinel, phlogopite, K-feldspar, plagioclase and variable quartz from Ihouhaouene (In Ouzzal, Algeria), display a range of decompression textures involving the breakdown of orthopyroxene and sillimanite, and of garnet. The succession of parageneses suggests that the P–T–t evolution corresponds to decompression with cooling from peak conditions of about 950°C and 10 kbar. This decompression path is obtained from the paragenetic analysis in the FMAS system. However, according to current KFMASH grids, this P–T–t evolution should take place outside the stability field of phlogopite+quartz; yet this assemblage is probably stable during most of the P-T evolution, notably during peak metamorphism. This discrepancy is interpreted as the effect of the high content of F in phlogopite which should shift its stability limit towards higher temperature. The consequences of this shift on the phase relationships in the KFeMASH system are investigated and it is concluded that a topological inversion could exist in the F-bearing system.  相似文献   

Calculation of Well Index for Nonconventional Wells on Arbitrary Grids     

Christian Wolfsteiner  Louis J. Durlofsky  Khalid Aziz 《Computational Geosciences》2003,7(1):61-82

Wells are seldom modeled explicitly in large scale finite difference reservoir simulations. Instead, the well is coupled to the reservoir through the use of a well index, which relates wellbore flow rate and pressure to grid block quantities. The use of an accurate well index is essential for the detailed modeling of nonconventional wells; i.e., wells with an arbitrary trajectory or multiple branches. The determination of a well index for such problems is complicated, particularly when the simulation grid is irregular or unstructured. In this work, a general framework for the calculation of accurate well indices for general nonconventional wells on arbitrary grids is presented and applied. The method entails the use of an accurate semianalytical well model based on Green's functions as a reference single phase flow solution. This result is coupled with a finite difference calculation to provide an accurate well index for each grid block containing a well segment. The method is demonstrated on a number of homogeneous example cases involving deviated, horizontal and multilateral wells oriented skew to the grid. Both Cartesian and globally unstructured multiblock grids are considered. In all these cases, the method is shown to provide results that are considerably more accurate compared to results using standard procedures. The method is also applied to heterogeneous problems involving horizontal wells, where it is shown to be capable of approximating the effects of subgrid heterogeneity in coarse finite difference models.  相似文献   

地形图数字化栅格影像的变形几何纠正关键算法研究   总被引：9，自引：0，他引：9  

孙开敏  陈艳  李德仁 《测绘信息与工程》2005,30(3):40-42

根据图幅号获得内图廓点、方里网格网点的理论地面坐标,通过改进的目标检测技术在地形图DRG中自动获得其影像坐标,使用内图廓点和方里网格网点构成Delaunay三角网进行影像纠正。  相似文献   

变质火山岩、火山碎屑岩的绿片岩相成岩格子和成岩格子的若干特征     

富公勤 《岩石矿物学杂志》1987,6(1):47-55

变质火山岩、火山碎屑岩的绿片岩相成岩格子可用阳起石—黑云母—方解石—绿泥石—绿帘石—白云母六相三元系和钠长石—阳起石—黑云母—方解石—绿泥石—绿帘石六相三元系成岩格子来表示,石英往往为过剩组分。在只讨论两个强度相同的变量前提下,每个六相三元系的成岩格子都只可能有一对成对的成岩格子,且这对成岩格子的非封闭双变区的分区相同、分区之间的边界斜率相同、相应的单变线的排列顺序也相同,因此,六相三元系的每个成岩格子中的不变点数、单变线数、和双变区数之间的关系可用数学式来表示。  相似文献   

Filter-Based Classification of Training Image Patterns for Spatial Simulation   总被引：16，自引：0，他引：16  

Tuanfeng Zhang  Paul Switzer  Andre Journel 《Mathematical Geology》2006,38(1):63-80

Multiple-point simulation, as opposed to simulation one point at a time, operates at the pattern level using a priori structural information. To reduce the dimensionality of the space of patterns we propose a multi-point filtersim algorithm that classifies structural patterns using selected filter statistics. The pattern filter statistics are specific linear combinations of pattern pixel values that represent directional mean, gradient, and curvature properties. Simulation proceeds by sampling from pattern classes selected by conditioning data.  相似文献   

Triangular Spectral Element simulation of two-dimensional elastic wave propagation using unstructured triangular grids     

E. D. Mercerat  J. P. Vilotte  F. J. Sánchez-Sesma 《Geophysical Journal International》2006,166(2):679-698

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适用于移动终端的全球离散格网快速生成方法     

陈浩  许长辉  宋现锋  徐江  潘苗苗 《测绘科学》2015,(12):63-67

针对全球离散格网依据剖分方法和投影方式的不同,在实现方式、剖分速度、格网均匀性等方面呈现出较大差异的问题,该文顾及移动终端用户对高精度位置应用日益增长的需求,以及顾及移动终端计算性能较低的特点,分析了球面格网生成方法、格网向椭球面投影方式和几何变形特点。通过分析椭球面格网与球面格网间变形差异,该文认为球面格网代替椭球面格网在一定程度上能够满足不同精度的格网剖分需求。通过建立用户精度指标与剖分层次对应关系,提高了格网剖分的计算效率,可应用于移动终端等计算性能较低的设备。  相似文献   

基于区块链的海洋数据安全共享系统构建          下载免费PDF全文

赵运星  赵强  黄超  杨涛  周广军  姜作真  胡丽萍 《海洋开发与管理》2023,40(1):37-43

在海洋数据体量快速积累和数据技术迅猛发展的时代背景下,海洋数据高效管理和价值挖掘成了重点课题之一。文章结合密码学中非对称加密技术(同态加密)和区块链中智能合约技术,构建“双链并行结合智能合约”的地区海洋数据安全共享系统。该双链系统中,“海洋数据注册链”管理共享节点、“海洋数据匹配链”管理待匹配节点,通过智能合约自动执行供需双方的资源有偿共享。该系统既促进了不同地区间的海洋数据共享流转,又保护了资源供应方的合法控制权,实现了对链上流通海洋数据的有效管理与监控,是区块链技术与传统海洋资源调查数据库相结合的海洋资源创新产物,理论上解决了不同地区间海洋经济发展中的海洋基础数据共享问题。  相似文献   

基于非结构网格剖分的海洋可控源电磁三维正则化反演研究          下载免费PDF全文

张洁  刘云鹤  殷长春  邱长凯  王青  李金峰 《地球物理学报》2019,62(11):4451-4461

为更好地处理与解释复杂海底地形条件下测得的海洋可控源电磁数据,本文提出了一种基于非结构网格剖分的频率域海洋可控源电磁数据三维正则化反演方法.该方法首先对海洋地电模型以非结构四面体单元进行离散,然后基于矢量有限元方法获得海洋可控源电磁响应和灵敏度信息,最后采用共轭梯度法求解高斯-牛顿反演方程计算模型修正量.为提高反演的稳定性,通过在反演过程中采用对数转换方法实现反演模型参数的上下限约束.本文分别测试了单测线水平海底地形反演算例和面积性测量的起伏海底地形反演算例.反演结果表明,本文提出的频率域海洋可控源电磁三维反演能够准确地恢复高阻储油层的位置和电阻率信息,且计算效率较高,可用于实测海洋电磁资料的处理与解释.  相似文献