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81.
GPS-OEM在精准农业领域中的应用实例   总被引：4，自引：0，他引：4  
介绍了我中心开发的内置有GPS—OEM板的农田信息采集系统，指出了GPS—OEM在精准农业领域发展潜力。  相似文献   
82.
阐述研究空间数据质量问题的必要性和重要性,进而依据GIS数据流程系统分析了产生数据质量问题的各种因素;并重点介绍了空间数据质量问题中基本的误差和不确定性分析方法以及常用的误差控制与校正方法。  相似文献   
83.
随着近年来计算机技术的发展,尤其是网络技术的发展,GIS在组成结构和应用技术等方面已与传统的GIS技术有了很大的不同,基于MapXtreme/MapX的WebGIS则是GIS技术发展的趋势。本文简单介绍WebGIS的发展趋势,结合一些例子介绍了利用MapXtreme的地理信息发布的技术和原理。  相似文献   
84.
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   
85.
This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model includes two major parts: (a) modeling the signal objects by STA-object elements, and (b) modeling relationships between STA-objects. As an example, the STA-model is applied for modeling land cover change data with spatial, temporal and attribute components.  相似文献   
86.
Point set generalization is one of the essential problems in map generalization. On the demands analysis of point set generalization, this paper proposes a method to generalize point sets based on the Kohonen Net model; the standard SOM algorithm has been improved so as to preserve the spatial distribution properties of the original point set. Examples illustrate that this method suits the generalization of point sets.  相似文献   
87.
Abstract

</p>Gamepads and joysticks have the potential to improve spatial navigation in virtual globes, block diagrams and 2D maps. Digital school atlases, in particular, can become more engaging if support for gamepads and joysticks is added, as children and adolescents are very proficient at using these devices. The fusion of gaming devices and interactive school atlases offers interesting new use cases: teachers can control a digital wall map with a remote-control gamepad while lecturing from the front of the classroom, or students can explore maps on their personal computers using an enticing way to interact. This paper presents these use cases, the characteristics of the most common gaming devices, and discusses spatial navigation with gamepads and joysticks for globes, block diagrams and 2D maps. The ideas presented originated from the ongoing development of a new, interactive version of the Swiss World Atlas for schools.  <a href="relate_search.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=A41A70F4AB56AB1B&aid=5A172168B32099AE544AB8BD3EC6ADF4&language=1&ctl=0&etl=29" target="_blank">相似文献</a>    </div> <div></div> <div class="clear"></div> </div> <div class="clear"></div> </div> <div class="search_article"> <div class="search_articleleft">88.</div> <div class="search_articleright"> <div> <a class="a1" href="https://td.alljournals.cn/view_abstract.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&aid=E21E6737789C2A77CDEA14F652F3DA65" target="_blank">Generation and study of satellite gravity over Gujarat,India and their possible correlation with earthquake occurrences</a>   <em><strong></strong></em>   </div> <div> <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=T.+J.+Majumdar" target="_blank">T. J. Majumdar</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=R.+Bhattacharyya" target="_blank">R. Bhattacharyya</a> <a class="a2" href="#">《国际地球制图》</a>2013,28(4):269-280 </div> <div>High-resolution satellite gravity data have been generated and utilized to infer subsurface geological structures in the area of devastating earthquake that struck the Bhuj region in Gujarat on 26 January 2001. Latitudinal gravity profiles have been generated in the Bhuj, Anjar and IBF regions across the epicentres (23.5° N, 69.8° E/M<sub>w</sub> 7.0 in 2001; 23.2° N, 70° E/M<sub>w</sub> 7.0 in 1956; 24.2° N, 69.2° E/M<sub>w</sub> 7.8 in 1819). Substantial differences in gravity anomaly patterns as high as 37 mGal could be observed existing near the epicentre regions. These gravitational differences might have caused due to the plate tectonic processes and due to the changes in densities of different lithospheric zones/sedimentary layers. Temporal variations of the satellite-derived gravity and their probable relations with already occurred major earthquakes in this region have been studied. Hence we conclude that drastic changes in gravity anomalies can be considered as a precursor for occurrences of substantially large earthquakes.  <a href="relate_search.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=A41A70F4AB56AB1B&aid=E21E6737789C2A77CDEA14F652F3DA65&language=1&ctl=0&etl=119" target="_blank">相似文献</a>    </div> <div></div> <div class="clear"></div> </div> <div class="clear"></div> </div> <div class="search_article"> <div class="search_articleleft">89.</div> <div class="search_articleright"> <div> <a class="a1" href="https://td.alljournals.cn/view_abstract.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&aid=94CB1CF5420CA8621FC2B6C9EFDA4DFC" target="_blank">规则格网DEM地形综合方法分析</a>   <em><strong></strong></em>   </div> <div> <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e5%be%90%e9%9d%99" target="_blank">徐静</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e9%a1%be%e7%95%99%e7%a2%97" target="_blank">顾留碗</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e5%bc%a0%e8%80%80%e6%b0%91" target="_blank">张耀民</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e9%9f%a9%e5%85%89%e8%be%89" target="_blank">韩光辉</a> <a class="a2" href="#">《测绘工程》</a>2014,23(9):26-31 </div> <div>针对当前丰富多样的DEM地形综合模型,分类阐述其综合原理、关键技术及优缺点,以黄土丘陵1：1万DEM为基础,对其地形综合效果进行对比分析。研究结果表明：现有的DEM地形综合模型各有优缺点;不同综合模型综合后的地形,高程数值随着综合尺度的增加,存在显著差异,而且不同综合模型对流域边界的综合处理也存在显著差异,没有形成客观有效的流域边界描述;当前困扰DEM地形综合的关键问题,是缺乏不同尺度下地形综合质量的客观评价标准,致使现有综合模型地形综合结果和DEM格网分辨率之间没有建立本应存在的内在联系,有待进一步深入研究。  <a href="relate_search.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=A41A70F4AB56AB1B&aid=94CB1CF5420CA8621FC2B6C9EFDA4DFC&language=2&ctl=15&etl=47" target="_blank">相似文献</a>    </div> <div></div> <div class="clear"></div> </div> <div class="clear"></div> </div> <div class="search_article"> <div class="search_articleleft">90.</div> <div class="search_articleright"> <div> <a class="a1" href="https://td.alljournals.cn/view_abstract.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&aid=8CBF77B6DF5F70EF4B84D0554BB233AC" target="_blank">空间坐标系变换的函数梯度描述方法</a>   <em><strong></strong></em>   </div> <div> <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e6%ae%b5%e9%b9%8f%e7%a1%95" target="_blank">段鹏硕</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e5%88%98%e6%a0%b9%e5%8f%8b" target="_blank">刘根友</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e9%be%9a%e6%9c%89%e4%ba%ae" target="_blank">龚有亮</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e9%83%9d%e6%99%93%e5%85%89" target="_blank">郝晓光</a>  <a href="search.aspx?subject=astronomy_earth_science&major=chx&field=author_name&encoding=utf-8&q=%e7%8e%8b%e5%a8%9c%e5%ad%90" target="_blank">王娜子</a> <a class="a2" href="#">《测绘学报》</a>2014,43(10):1005-1012 </div> <div>为了将空间坐标系变换由静态的、不随时间发生变换的情况推广到动态的、随时间发生变换以及任意角度发生变换的情况,基于单位四元数构造的旋转矩阵和罗德里格矩阵的完全等价性,揭示出空间坐标系（空间直角坐标系）变换与函数梯度的数学关系,推导出由函数梯度表示的空间坐标系变换的数学公式,在理论上说明了用函数梯度描述空间坐标系变换的方法。研究表明：在数学意义上,空间坐标系变换的本质是"场",可以用"场"的概念统一以任意角度发生旋转变换的空间坐标系变换特例。为进一步研究空间坐标系随时间发生连续变换的情况或以新的思路为运动载体定姿奠定了理论基础。  <a href="relate_search.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=A41A70F4AB56AB1B&aid=8CBF77B6DF5F70EF4B84D0554BB233AC&language=2&ctl=16&etl=79" target="_blank">相似文献</a>    </div> <div></div> <div class="clear"></div> </div> <div class="clear"></div> </div> <div> <div class="search_article_pager"> <a href="search.aspx?start=0&q=spatial information technology&field=key_word&subject=astronomy_earth_science&major=twxdqkxxbjzhl">[首页]</a> <a 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