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31.
为解决目前医院地理信息服务系统在信息共享、空间分析等方面的不足,采用ArcGIS Server组件、C#编程语言、SQL Server数据库研发了医院网络地理信息服务系统。该系统以天地图作为基础地理数据,融合医院空间与医疗信息,并部署到互联网环境中。除具有医疗专题信息的网络浏览与查询外,系统还实现了诸多空间分析、地学统计等功能,既可为市民就医提供更全面的信息查询,又可为医疗事故的突发与应急提供技术支撑。 相似文献
32.
Data refinement refers to the processes by which a dataset’s resolution, in particular, the spatial one, is refined, and is thus synonymous to spatial downscaling. Spatial resolution indicates measurement scale and can be seen as an index for regular data support. As a type of change of scale, data refinement is useful for many scenarios where spatial scales of existing data, desired analyses, or specific applications need to be made commensurate and refined. As spatial data are related to certain data support, they can be conceived of as support-specific realizations of random fields, suggesting that multivariate geostatistics should be explored for refining datasets from their coarser-resolution versions to the finer-resolution ones. In this paper, geostatistical methods for downscaling are described, and were implemented using GTOPO30 data and sampled Shuttle Radar Topography Mission data at a site in northwest China, with the latter’s majority grid cells used as surrogate reference data. It was found that proper structural modeling is important for achieving increased accuracy in data refinement; here, structural modeling can be done through proper decomposition of elevation fields into trends and residuals and thereafter. It was confirmed that effects of semantic differences on data refinement can be reduced through properly estimating and incorporating biases in local means. 相似文献
33.
乔柱 《测绘与空间地理信息》2013,(3):157-159
随着城市建设的飞速发展,社会对城市基础信息的需求日益增加,传统的数字化测绘难以满足现代信息化测绘的需求。佛山市信息化测绘基础软件在实现信息数据的集成化、信息处理自动化、信息应用社会化等方面做出了巨大的贡献,本文从该软件在大比例尺测绘中针对房屋的切片管理及属性管理展开,重点论述了信息数据的集成化管理及应用。 相似文献
34.
35.
本文探讨了在全省范围内通过统一建设的方式,以国土云为核心,抓好顶层设计,统筹规划、统一建设推进基层国土资源信息化建设,对于加快国土资源部门基层信息化应用发展具有重要的参考价值. 相似文献
36.
介绍了利用ArcObjects开发、基于ArcScene的建筑物日照分析模块的研制,对各个子模块作了介绍。特别对涉及到的日照分析技术、阴影动态显示、3维建筑设计等技术做了详细的说明。最后对该模块的应用做了简要演示。 相似文献
37.
Synthetic aperture radar (SAR) image formation for a ground moving target necessitates the compensation of the unknown target trajectory. The keystone transform has been employed to remove the linear component of the range migration for the moving target, where interpolation is required. In this letter, a realization of the keystone transform avoiding interpolation is presented. The kernel of this transform, i.e., the range-frequency-dependent azimuth time rescaling, is implemented using only complex multiplications and fast Fourier transforms based on the scaling principle, which has been successfully applied in the equalization of the space-variant range cell migration in SAR processing. In addition, the moving target is coarsely focused according to the SAR geometry and the platform velocity while exploiting the scaling principle. This preliminary focusing is helpful in the isolation of the moving target from ground clutter, so as to facilitate a more refined processing with respect to each mover. SAR raw data combined with simulated echoes of moving targets are utilized to validate the presented approach 相似文献
38.
Min Zhu Wadge G. Holley R.J. James I.N. Clark P.A. Changgui Wang Woodage M.J. 《Geoscience and Remote Sensing Letters, IEEE》2007,4(3):401-405
Propagation delay due to variable tropospheric water vapor (WV) is one of the most intractable problems for radar interferometry, particularly over mountains. The WV field can be simulated by an atmospheric model, and the difference between the two fields is used to correct the radar interferogram. Here, we report our use of the U.K. Met Office Unified Model in a nested mode to produce high-resolution forecast fields for the 3-km-high Mount Etna volcano. The simulated precipitable-water field is validated against that retrieved from the Medium-Resolution Imaging Spectrometer (MERIS) radiometer on the Envisat satellite, which has a resolution of 300 m. Two case studies, one from winter (November 24, 2004) and one from summer (June 25, 2005), show that the mismatch between the model and the MERIS fields ( rms = 1.1 and 1.6 mm, respectively) is small. One of the main potential sources of error in the models is the timing of the WV field simulation. We show that long-wavelength upper tropospheric troughs of low WV could be identified in both the model output and Meteosat WV imagery for the November 24, 2004 case and used to choose the best time of model output. 相似文献
39.
本文分析了Adobe Flash技术在网络地图发布前端技术上的优势和应用现状,选择开源Flash地图组件Modest Maps作为开发工具,在其上添加了一些组件模块,以"5.12地震信息显示"为示例,实现了基于Modest Maps的Falsh网络地图发布和简单的空间分析. 相似文献
40.
WANG Ren ZHU Xinhui 《地球空间信息科学学报》2007,10(1):57-60
In the field of converting simulation surveying and traditional close range photogrammetry, it has been developed so far to survey objects by commercial digital camera and this technique is applied widely in every part of production. In order to get three-dimensional information of objects, commercial digital camera must be examined. For a long time, digital camera has been examined by DLT. Then there must be a high-precision control field. For realizing surveying without control points, a method for self-calibration is proposed. 相似文献