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关于数字地质图元数据编制方法若干问题的讨论 总被引：1，自引：0，他引：1
为实现空间数据共享，需要描述空间数据或数据集的内容、质量、状态和其他特性的数据，这就是元数据。以编制中国1：50万数字地质图空间数据库元数据的实际经验，结合国内外已有的资料，分析了数字地质图空间数据库元数据的特点、用途和编制方法，提出了进一步改进的建议。 相似文献
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为实现空间数据共享,需要描述空间数据或数据集的内容、质量、状态和其他特性的数据,这就是元数据.以编制中国1∶50万数字地质图空间数据库元数据的实际经验,结合国内外已有的资料,分析了数字地质图空间数据库元数据的特点、用途和编制方法提出了进一步改进的建议. 相似文献
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基于地学G~4I系统的元数据分类方法 总被引：1，自引：0，他引：1
以实现空间数据的标准化为前提,对空间数据库中元数据管理系统的作用和分类原则进行了探讨,指出了传统的分类方法对于以矿产资源预测为目标的地学系统而言存在着弊端。需要结合矿产资源预测的特点,对空间数据库建设中元数据的分类原则进行补充,提出了面向客户应用即按矿产资源预测目标进行分类,实现对空间数据查询的高效利用。该方法可以在地学G4I系统中得以实施和应用。 相似文献
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为了解决分布式地质图空间数据库之间的数据共享和一致性维护问题,在MAPGIS7 .0面向地理实体的空间数据模型的基础上,根据地质图空间数据组织和分布的特点设计了一种“横向网格、纵向多级”的分布式多级服务器组网方案,结合该方案提出了一种以地质空间要素类为单位,面向服务的数据交换策略.该策略在国家地质调查空间数据库管理系统中的应用表明:以要素类为基本数据交换单位可以有效地维护分布式地质数据的空间、拓扑和语义的一致性;以服务的方式操作使数据交换能够跨平台、跨操作系统以及适合异构数据库.实践证明,这种策略是适合于分布式地质图空间数据库的一体化组织与管理的. 相似文献
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地学G4 I 系统是以四学科( 地质学、地理学、地球化学及地球物理学) 地学数据集成为基础,以中大比例尺矿产资源评价为服务目标的计算机系统。由于跨学科地学空间数据集成涉及到众多技术,其中空间元数据的内容与应用构成本系统的重要组成部分。笔者就元数据的概念及元数据在本系统中的具体内容、作用、标准及研究现状等进行探讨,并针对本系统提出元数据管理子系统的设计框架。 相似文献
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通过山西省1∶5万矢量数据库的设计过程,阐述其中的核心技术。基于Oracle+ArcSDE的技术建立的空间数据库技术是一种比较成熟的、稳定的空间数据库管理技术,也是省级基础地理数据库的主流模式。ArcSDE作为中间插件联系应用程序和关系数据库,解决了空间数据和属性数据统一存储。 相似文献
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中国岩石圈三维结构数据库元数据的设计与管理 总被引：2，自引：2，他引：2
中国岩石圈三雏结构数据库基于ArcGIS平台。为进行项目的空间数据规范化管理，通过时FGDC标准和ESRI规范的元素项作了适当取舍和简化。制定了项目的空间数据元数据标准，该标准和FGDC标准兼容；用ArcObjects编程实现了专用的元数据编辑器；编制项目专用XSL样式表。使用ArcGIS系统的同步程序及定制的元数据编辑器实现了空间数据的元数据管理。 相似文献
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Many applications involving spatial data require several layers of information to be simultaneously analyzed in relation to underlying geography and topographic detail. This in turn generates a need for forms of multivariate analysis particularly oriented to spatial problems and designed to handle spatial structure and dependency both within and between spatially indexed multivariate responses. In this paper we focus on one group of such methods sometimes referred to as spatial factor analysis. Use of these techniques has so far been mostly restricted to applications in the geosciences and in some forms of image processing, but the methods have potential for wider use outside these fields. They are concerned with identifying components of a multivariate data set with a spatial covariance structure that predominantly acts over a particular spatial range or zone of influence. We review the various forms of spatial factor analysis that have been proposed and emphasize links between them and with the linear model of coregionalization employed in geostatistics. We then introduce extensions to such methods that may prove useful in exploratory spatial analysis, both generally and more specifically in the context of multivariate spatial prediction. Application of our proposed exploratory techniques is demonstrated on a small but illustrative geochemical data set involving multielement measurements from stream sediments. 相似文献
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Oracle Spatial几何类型字段解析 总被引：4，自引：0，他引：4
Oracle Spatial是Oracle数据库中管理空间数据的模块,它采用SDO_GEOMETRY字段存储空间数据。Oracle Spatial更深层次的功能,如索引、查询等,都建立在SDO_GEOMETRY的存储机制上。这里详细介绍了Oracle Spatial中空间对象字段SDO_GEOMETRY的组成及其各个组成对象的定义方法,解析了点(包括复合点)、线(包括复合线)、多边形(包括复合多边形)等空间实体在SDO_GEOMETRY中的存储方式,为其它编程语言访问Oracle Spatial空间对象提供了参考。 相似文献
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地质图空间数据库的建立是我国从纸制地质图件向多源地学空间信息数据库转变的一个标志,为多源地学信息综合分析和解释提供了充足的数据源。将建平幅以往大量的数据纸介质整理后进行属性数据、图形数据采集,建立了一个能够随意提取、可以不断更新的地质图件库,分析讨论了地质图数据库的特点、功能,并进行了应用。 相似文献
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A Spatial Analysis Neural Network (SANN) algorithm was applied for the analysis of geospatial data, on the basis of nonparametric statistical analysis and the concepts of traditional Artificial Neural Networks. SANN consists of a number of layers in which the neurons or nodes between layers are interconnected successively in a feed-forward direction. The Gaussian Kernel Function layer has several nodes, and each node has a transfer or an activation function that only responds (or activates) when the input pattern falls within its receptive field, which is defined by its smoothing parameter or width. The activation widths are functions of the model structural parameters, including the number of the nearest neighbor points P and a control factor F. The estimation method is based on two operational modes, namely, a training-validation mode in which the model structure is constructed and validated, and an interpolation mode. In this paper we discuss the effect of varying F and P upon the accuracy of the estimation in a two-dimensional domain for different input field sizes, using spatial data of wheat crop yield from Eastern Colorado. Crop yield is estimated as a function of the two-dimensional Cartesian coordinates (easting and northing). The results of the research led to the conclusion that optimal values of F and P depend on the sample size, i.e., for small data sets F=1.5 and P=7 while for large data sets F=2.5 and P=9. In addition, the accuracy of the interpolated field varies with the sample size. As expected for small sample sizes, the interpolated field and its variability may be significantly underestimated. 相似文献
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Barry Boots 《GeoJournal》2001,53(4):339-345
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Geostatistics has traditionally used a probabilistic framework, one in which expected values or ensemble averages are of primary importance. The less familiar deterministic framework views geostatistical problems in terms of spatial integrals. This paper outlines the two frameworks and examines the issue of which spatial continuity measure, the covarianceC (h) or the variogram (h), is appropriate for each framework. AlthoughC (h) and (h) were defined originally in terms of spatial integrals, the convenience of probabilistic notation made the expected value definitions more common. These now classical expected value definitions entail a linear relationship betweenC (h) and (h); the spatial integral definitions do not. In a probabilistic framework, where available sample information is extrapolated to domains other than the one which was sampled, the expected value definitions are appropriate; furthermore, within a probabilistic framework, reasons exist for preferring the variogram to the covariance function. In a deterministic framework, where available sample information is interpolated within the same domain, the spatial integral definitions are appropriate and no reasons are known for preferring the variogram. A case study on a Wiener-Levy process demonstrates differences between the two frameworks and shows that, for most estimation problems, the deterministic viewpoint is more appropriate. Several case studies on real data sets reveal that the sample covariance function reflects the character of spatial continuity better than the sample variogram. From both theoretical and practical considerations, clearly for most geostatistical problems, direct estimation of the covariance is better than the traditional variogram approach.This paper was presented at MGUS 87 Conference, Redwood City, California, 14 April 1987. 相似文献
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An Experimental Comparison of Ordinary and Universal Kriging and Inverse Distance Weighting 总被引：17，自引：0，他引：17
A factorial, computational experiment was conducted to compare the spatial interpolation accuracy of ordinary and universal kriging and two types of inverse squared-distance weighting. The experiment considered, in addition to these four interpolation methods, the effects of four data and sampling characteristics: surface type, sampling pattern, noise level, and strength of small-scale spatial correlation. Interpolation accuracy was measured by the natural logarithm of the mean squared interpolation error. Main effects of all five factors, all two-factor interactions, and several three-factor interactions were highly statistically significant. Among numerous findings, the most striking was that the two kriging methods were substantially superior to the inverse distance weighting methods over all levels of surface type, sampling pattern, noise, and correlation. 相似文献
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基于证据权法构建滑坡地质灾害评价模型,进行杭州市滑坡地质灾害危险性区划研究。主要数据源包括1930－2009年杭州市域采集到的1 905个地质灾害个例以及杭州市地质图、土地利用数据及数字高程模型（DEM）等。利用Arcgis空间分析及信息提取功能,筛选强降水、地层岩性、坡度、坡向、坡高、河网与道路缓冲等证据因子,并运用证据权法客观确定各因子权重, 最后通过Arc-WofE扩展模块对多种优选因子的叠加,计算任意格网单元的滑坡发生概率,实现对潜在滑坡点位的空间预测。经分离样本法验证,区划准确率为88.3%,分析结果与现有滑坡的分布情况比较吻合。据此表明证据权法在多指标评价及其权重确定等方面具有普适性,值得在滑坡地质灾害危险性区划等方面推广应用。 相似文献