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排序方式: 共有151条查询结果,搜索用时 15 毫秒
41.
网络环境下测绘数据三库一体化的研究与实践   总被引:5,自引:0,他引:5  
文中利用Oracle 8中的多媒体特性 ,就三库一体化中正射影像数据库、分要素层矢量数据库和格网DEM数据库的建立进行了探讨。主要解决了矢量源数据入库前的组织、DEM数据与ORDimage类型的转换、跨带自动拼接等关键问题  相似文献   
42.
Big Data Analytics for Earth Sciences: the EarthServer approach   总被引:1,自引:0,他引:1  
Big Data Analytics is an emerging field since massive storage and computing capabilities have been made available by advanced e-infrastructures. Earth and Environmental sciences are likely to benefit from Big Data Analytics techniques supporting the processing of the large number of Earth Observation datasets currently acquired and generated through observations and simulations. However, Earth Science data and applications present specificities in terms of relevance of the geospatial information, wide heterogeneity of data models and formats, and complexity of processing. Therefore, Big Earth Data Analytics requires specifically tailored techniques and tools. The EarthServer Big Earth Data Analytics engine offers a solution for coverage-type datasets, built around a high performance array database technology, and the adoption and enhancement of standards for service interaction (OGC WCS and WCPS). The EarthServer solution, led by the collection of requirements from scientific communities and international initiatives, provides a holistic approach that ranges from query languages and scalability up to mobile access and visualization. The result is demonstrated and validated through the development of lighthouse applications in the Marine, Geology, Atmospheric, Planetary and Cryospheric science domains.  相似文献   
43.
1 IntroductionAtpresent,digitalorthoimagesandorthoimagemosaicsareplayinganincreasinglyimportantrolethroughouttheentiregeoinformationdomain .Es peciallyafterthetermdigitalearthisputforward ,digitalorthoimagesbecomethemaincontentofdigitalearthaswell.Orthoi…  相似文献   
44.
GeoStar is the registered trademark of GIS software made by WTUSM in China.By means of the GeoStar,multi-scale images,DEMs,graphics and attributes integrated in very large seamless databases can be created,and the multi-dimensional dynamic visualization and information extraction are also available.This paper describes the fundamental characteristics of such huge integrated databases,for instance,the data models,database structures and the spatial index strategies.At last,the typical applications of GeoStar for a few pilot projects like the Shanghai CyberCity and the Guangdong provincial spatial data infrastructure (SDI) are illustrated and several concluding remarks are stressed.  相似文献   
45.
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   
46.
Introduction Seismic monitoring is one of the most important approaches for ground-based nuclear explo-sion monitoring (CTBTO, 1998). The trend in this research field is to improve the monitoring ca-pability for low magnitude seismic events in regional scales. Seismic monitoring mainly includes detection, location, identification and characterization of seismic events. The correctness and accuracy of all of them depend on the quality of seismic re-cords and the degrees of uncertainties of ge…  相似文献   
47.
简述了信息技术与地学的发展现状,并对MAPGIS进行展望。  相似文献   
48.
讨论了在地籍信息系统(Cadastral Information System简称CIS)中如何应用统一建模语言(Un ified Model-ing Language简称UML)设计关系数据库(Relational Database简称RDB),并结合CIS中的属性数据,给出一个简单实例,为CIS的数据库设计提供一种参考。  相似文献   
49.
A database for pulsating variable stars is constructed to favor the study of variable stars in China. The database includes about 230,000 variable stars in the Galactic bulge, LMC and SMC observed in an about 10 yr period by the MACHO(MAssive Compact Halo Objects) and OGLE(Optical Gravitational Lensing Experiment) projects. The software used for the construction is LAMP, i.e., Linux+Apache+MySQL+PHP. A web page is provided for searching the photometric data and light curves in the database through the right ascension and declination of an object. Because of the flexibility of this database, more up-to-date data of variable stars can be incorporated into the database conveniently.  相似文献   
50.
Many of the world’s deserts were transformed by irrigation expertise at the beginning of the 20th century. An irrigation “technological zone” emerged to facilitate the circulation of engineering expertise and the territorial expansion of the U.S. and British imperial states. Hydraulic engineers considered themselves globally connected technicians providing practical solutions to the political problems of poverty and famine. Although premised on the neutrality and universal applicability of scientific principles, the practices and environmental expertise of irrigation engineers were firmly rooted in regional state/society formations, which sought to increase agricultural production and induce settlement with irrigation. This paper analyzes the globalization of irrigation expertise through a relational comparison of the irrigation narratives of the British Punjab and the Western U.S., 1880–1920. The analysis demonstrates that the irrigation technological zone was significantly formed by place-based dynamics that, in turn, shaped irrigation as a mode of environmental expertise.  相似文献   
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