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XUCaijun LIZhicai WANGQi 《地球空间信息科学学报》2005,8(1):1-7
Combining the dense GPS and gravity observation data in Sichuan-Yunnan area, where there are the relatively complete active tectonic zones and seismic data, this paper applies the geodesy and geophysical inversion technique and the advanced numerical simulation to the synthesis study of geodesy inversion to find the dynamic process of tectonic movement and deformation in the area and finally to investigate the kinematics characteristic of the geological structure of different layer and different scale. This paper discusses the kinematics, dynamics model about the crustal movement of active blocks in Sichuan-Yunnan area and its adjacent areas. 相似文献
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CHEN Lei 《地球空间信息科学学报》2008,11(3):228-234
A review was conducted on the environmental evolvement and environmental archaeological research since the 1980s in the Yangtze Delta. Former environmental evolvement and environmental archaeological research results can be summed up into 4 aspects： 1） Formation and evolution of the Taihu Lake; 2） Transgression and sea-level changes in the Holocene epoch; 3） Reconstruction of the pre-historical environment; and 4） Impacts of environmental variations on the rise and fall of human civilization （formation of the cultural interruptions）. Based on this review, some limitations in the present research methods and possible outcomes are pointed out in this paper. 相似文献
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DerenL 《地球空间信息科学学报》1998,(1)
In recent years,China has experienced unprecedented expansion in its econo-my,which has resulted in rapid development of its culture,education andtechnology through implementing the policy of reform and opening initiated byDeng Xiaoping.The development of science and technology has promoted thelevel of the productive force and the great achievements in China have become oneof the focuses of the world.Enhancements of science and technology in the coun-try and active external communication have raised the international status of Chi- 相似文献
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LIJianping ZHANGBai GAOFeng 《地球空间信息科学学报》2005,8(2):104-109
By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM- image in 2001 from American LANDSAT satellite, all kinds of maps and documentation, information of grassland, saline-alkalized land, cropland, water area and forestland is extracted by man-computer interactive interpretation method with ArcView and Arclnfo GIS software, and statistics data is acquired. On the basis of this the changing trend of land use types in the next ten years is forecasted and analyzed with Markov model. The results indicate that the problem of grassland degradation in the study area is quite serious. 相似文献
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LI Deren 《地球空间信息科学学报》2012,15(1)
Modern scientific research mainly focuses on three themes:materials,energy,and information.The concept of information was coined in the 1920s.Breakthroughs in information technology and the creation of information theory in the 1940s presaged an information age,when research and applications of information theory and technology began in full swing.Since the 1950s,the information revolution wave has swept across the world.By the early 1990s,with a booming information industry,information concepts and information technology permeated all walks of life.Social information networks based on the information super highway have accelerated the pace of construction and development in many countries;the information revolution has demonstrated bright prospects for human beings. 相似文献
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WUXiaofang CAIZhongliang WUGuofeng DUQingyun 《地球空间信息科学学报》2003,6(4):27-31
Through analyzing the principle of data sharing in the database system, this paper discusses the principle and method for integrating and sharing GIS data by data engine, introduces a way to achieve the high integration and sharing of GIS data on the basis of VCT in VC , and provides the method for uniting VCT into RDBMS in order to implement a spatial database with object-oriented data model. 相似文献
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《测绘学报》1988,(2)
（Provisional）Ⅰ.Chinese Society of Geodesy, Photogrammetry and Cartography (CSGPC) is an academicmass organization which may be joined voluntarily by scientists and experts at accepting geodesists,photogrammetrists, cartographers and on surveying and mapping. The establishment of correspondingmembership in the society aims surveyors of great attainments in the world as members in order todiscuss and exchange views on academic issues in surveying and mapping, to promote friendship andcooperation between surveyors and to make contributions to the four modernizations in China andto the welfare of mankind. 相似文献
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《测绘学报》1988,(3)
（Provisional）Ⅰ.Chinese Society of Geodesy, Photogrammetry and Cartography (CSGPC) is an academicmass organization which may be joined voluntarily by scientists and experts at accepting geodesists,photogrammetrists, cartographers and on sureying and mapping. The establishment of correspondingmembership in the society aims surveyors of great attainments in the world as members in orderto discuss and exchange views on academic issues in surveying and mapping, to promote friendshipand cooperation between surveyors and to make contributions to the four modernizations in Chinaand to the welfare of mankind. 相似文献
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《地图》1989,(2)
China Cartographic Publishing House is the nation's central-level and largest press specialized in compiling and publishing small-scale maps and atlases. Founded in 1954, the house has up to now a history of 35 years. It was moved from the eastern part of Beijing to the present site in southwest Beijing in 1960. With a total built area of over 20,000 square metres, the house consists of two working buildings and some subsidiary 相似文献
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Guan Jihong 《地球空间信息科学学报》2013,16(2):118-126
GML is becoming the de facto standard for electronic data exchange among the applications of Web and distributed geographic information systems. However, the conventional query languages (e.g. SQL and its extended versions) are not suitable for direct querying and updating of GML documents. Even the effective approaches working well with XML could not guarantee good results when applied to GML documents. Although XQuery is a powerful standard query language for XML, it is not proposed for queryings spatial features, which constitute the most important components in GML documents. We proposes GQL, a query language specification to support spatial queries over GML documents by extending XQuery. The data model, algebra, and formal semantics as well as various spatial functions and operations of GQL are presented in detail. 相似文献
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基于XQuery的GML查询语言研究 总被引：4，自引：0，他引：4
随着GML规范的不断完善及GIS软件厂商的广泛支持,越来越多的空间数据以GML格式存储,GML空间数据的查询已成为GIS研究的热点问题。传统的关系数据库查询语言SQL是针对平面的二维关系数据而设计的,并不适合XML/GML半结构化数据的查询;商品化GIS软件的查询系统只能查询自身的空间数据而无法查询其它GIS系统的空间数据;XML查询的研究为GML查询奠定了一定的基础。首先针对GML查询存在的问题,提出了扩展XQuery是GML查询语言实现的最佳选择;结合XML查询语言和空间数据查询语言,提出了GML查询语言的特征和GML查询语言系统框架;并根据GML空间数据的特点,以XML标准查询语言XQuery为基础,提出了XQuery空间扩展的内容;开发了GML空间数据查询语言GMLXQL,实现了GML空间数据的本原查询。 相似文献
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GML空间数据查询与索引机制研究 总被引：9，自引：0，他引：9
由于传统GIS数据模型的差异，导致空间数据难以集成与共享。各GIS软件厂商及第三方软件厂商提出了利用空间数据转换的解决方案，但是它还是不能很好地解决空间数据集成与共享存在的问题。地理标记语言GML的出现，为GIS空间数据建模、集成与共享提供了统一的标准与框架。GML已经成为事实上的空间数据编码、传输、存储和发布的国际标准，大量GML格式的空间数据开始涌现。如何有效地存储管理GML空间数据，已经成为GIS研究的热点问题。本文结合XML数据库技术和传统的空间数据库技术，对GML空间数据的查询、索引进行了深入的研究。以XML标准查询语言XQuery为基础，提出了XQuery空间扩展的内容，开发了GML空间数据查询语言，实现了GML空间数据的本原查询；结合XML文档编码和传统的空间数据索引，提出了基于空间索引的GML一体化索引机制，并以R树索引为例，对一体化索引的查询处理性能进行了实验分析。实验结果表明，本文提出的基于空间索引的GML一体化索引机制是可行的、高效的。 相似文献
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广泛运用Web和分布式地理信息系统(WGIS/DGIS)有利于共享的空间数据库组织之间和用户通过互连网进行数据交换。不过,这些系统和应用软件的互操作性仍然是一个不能解决的问题,直到最近出版的地理标记语言(GML)标准的出现,这一问题才得到了解决。GML是一个新的实施规范并提供中立的框架为定义地理空间应用模式和对象的可扩展标记语言(XML)的文档。XML迅速成为一个事实上的标准电子数据交换之间的Web应用程序,然而,传统的数据库查询语言,在其目前的形式下并不适合直接查询和更新XML库。由W3C提出的XQuery查询语言为XML提供了强大的查询功能,但它缺乏支持空间查询,本文主要研究具有空间查询的语言GML-QL。 相似文献
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Currently,the OGC GML(Geography Markup Language) specification has been the de facto standard for GIS data sharing and exchanging and spatial interoperation.Adopting nested association expression approach of XML data,GML data documents can store both spatial information and semantic relationship information of geographical elements.To improve the efficiency of path query on GML two type information,the paper describes a holistic index method for GML data,which we call EKR+(optimized R+-tree base on Extend R... 相似文献
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在分析土地房产要素特点的基础上．探讨了土地房产空间要素的GML模型及其应用。基于GML语言设计了土地房产空间要素的XML Scenma模式．定义和描述了土地房产要素及其属性．探讨了基于XML和XQuery实现大数据量的地籍对象查询．利用Java DOM和SAX开发了一个基于GML的土地房产GIS系统．实现了土地房产权籍要素图形和属性的一体化管理系统应用表明了所提出的模型和实现是可行的。 相似文献