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241.
Geographic information has a great potential to be re-used when supported by mechanisms for its discovery. Above all, the quality of a catalogue service is the key feature supporting users in the discovery process. So far, there have been in existence various methodologies dealing with the normalized evaluation of quality with respect to catalogue services. Their biggest weakness seems to be in the depth of quality testing, i.e. some influences are beyond the scope of evaluation of these methodologies with respect to quality in catalogue services. In this study, the quality of 45 catalogue services across Europe was verified with the proposed normalized evaluation methodology originating from documents within the INfrastruture for SPatial InfoRmation in Europe (INSPIRE) framework. This paper discusses the (statistical) influence of factors that may significantly change the results of catalogue service testing. The proposals for improving the existing INSPIRE normalized evaluation procedure are applicable for any spatial data infrastructure and/or Digital Earth component using the Open Geospatial Consortium Catalogue Service for the Web as a basis. 相似文献
242.
随着越来越多基于网络、自动化的信息共享系统的广泛使用,元数据已成为不同学科间共享信息的关键。近年来气象数据的应用领域不断扩展,气象数据面临着海量信息流通共享的迫切需要,由此气象元数据应运而生。该文介绍的气象元数据是在满足WMO (世界气象组织) 信息系统提出的包括提供在线元数据、数据目录服务和提高元数据定义、收集、归档和交换的标准化水平在内的总体需求的背景下,依据WMO核心元数据标准设计并由自开发程序自动生成的。北京GISC系统是WMO信息系统中承担区域间及全球资料交换的主干通信中心之一,至2012年1月,北京GISC系统制作并提供系统内全部数据对应的气象元数据,共计约12万条。 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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电子政务数据资源的开发利用 总被引：8，自引：0，他引：8
如何使已有的政务数据实现有效共享并通过数据挖掘转变为知识和财富已经成为电子政务建设的一个关键内容。该文分析了电子政务数据资源开发利用的重要性，建议尽快制订政务元数据标准，以促进政务数据共享。提出了电子政务数据仓库的体系结构和建设内容，并且认为把分布式数据挖掘技术引入电子政务中对于政府决策支持意义重大。 相似文献
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Goal and Scope. The UNECE heavy metals in Mosses Surveys provide data on the accumulation of metals in naturally growing mosses throughout Europe. Using Germany as an example, this article concentrates on the elaboration and application of methods of data analysis that are necessary for a comprehensive interpretation of spatial and temporal trends in metal accumulation.Methods and Results. The sampling of mosses, and the chemical analysis of Cr, Cu, Fe, Ni, Pb, Ti, V and Zn in 1990, 1995 and 2000 are summarized briefly. The variogram analyses detect distinct autocorrelation structures in the sample data which may consequently be estimated for all sites in Germany without monitoring metal accumulation by means of ordinary kriging. A procedure for the geostatistical detection of spatial outliers was developed and applied and, after the elimination of the spatial outliers, several measurements were seen to indicate an adequate quality of the geostatistical estimations. The cluster analyses of the z-transformed estimation data result in a nominal multi-element index that indicates regional metal accumulation types over time. Percentile statistics serve for computation of an ordinal, scaled, multi-element accumulation index which is spatially differentiated over time in terms of multivariate, statistically defined ecoregions. The integrative statistical analysis reveals, from 1990 to 2000, that the metal accumulation declines up to 80% in some of the ecoregions. Hot spots of metal accumulation are mapped and interpreted by means of metadata analysis.Conclusions. Dot maps depict the spatial structure of the metal accumulation without spatial bias. This information, detailed with respect to metal species and space, should be generalized for better supporting the interpretation. The combination of geostatistical analysis and estimation, percentile and multivariate statistics is suitable for the calculation of indices that serve for a comprehensive mapping of metal accumulation in the ecoregions over time, for quantifying the bias of the surface estimation, and for mapping spatial outliers and hot spots of metal accumulation. 相似文献
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