排序方式： 共有144条查询结果，搜索用时 31 毫秒
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基于Google Earth地图数据,采用C#语言进行二次开发提取高程数据信息,应用于农村土地整理规划设计,为充分、合理和高效进行农村土地整理提供了技术保障,提高了农村土地利用效率。 相似文献
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Google Earth® provides free access to satellite images and has been used in several areas that require cartographic information. The present study assessed the inconsistencies between geo-referencing of livestock premises by GPS and the acquisition of geographic coordinates by remote sensing (RS) images provided by Google Earth® in the Brazilian states of Bahia, Distrito Federal, Minas Gerais and Parana. The overall mean and standard deviation of the distances in the study were 30.98 ± 19.89 m. The mean distance differences between the two techniques were, for these states, 37.20 ± 19.75 m, 28.38 ± 17.38 m, 31.61 ± 15.72 m, 28.43 ± 24.30 m, respectively. Despite the fact that there is variation between the geo-referencing points using GPS and RS, geographical localization of health inspections should be useful as long as the errors between the results of the two methodologies are considered. 相似文献
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李伟 《农业图书情报学刊》2008,20(3):94-95
介绍了当前Google的网络图书馆发展状况,分析了其迅速发展的背景和原因,以及对传统高校图书馆的冲击,提出了在新形式下高校图书馆要挖掘潜力,发挥自身优势的思路. 相似文献
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基于Google Maps API的Web地图服务的应用范围已经从大的门户网站扩展到小的个性社区、博客站点,成为网站构建者十分青睐的一种方式,但在备受关注的沙漠化研究领域却很少涉足。沙漠化是人类当今所面临的重大环境与社会问题之一,已经成为制约地区经济可持续发展的主要限制因素。本研究以四川西北部若尔盖地区为例,提出以Google Maps Web地图做为信息平台的地理信息系统。系统拥有视图、属性表、统计图表和图形等功能,为研究沙漠化的现状及危害程度,预测沙漠化发展趋势并规划防沙治沙措施提供了数据和图表参考依据。 相似文献
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监测预警是三峡库区地质灾害防治的主要措施,对其产生的海量信息进行有效管理是对库区进行有效防灾减灾和管理决策的基础。Google Earth作为一款免费提供全球三维遥感影像数据的虚拟地球软件平台,在对地质灾害专业监测预警信息集成管理和展示方面具有成本低、实施快、展示逼真等优点。在分析三峡库区地质灾害专业监测数据组成及其安全性、用户可视化的空间认知过程和习惯等的基础上,提出了三峡库区地质灾害专业监测预警信息集成方案,并利用Google Earth提供的功能予以实现,取得了较好的效果,也表明Google Earth在地质灾害信息集成、管理和展示等方面具有广阔的应用前景。 相似文献
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GOOGLE SCHOLAR和国学百度是两个重要的搜索引擎,本文介绍了他们各自的特点,并分析了其在学术检索中各自的作用。并从使用者的角度分析了两个引擎的不足之处。 相似文献
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Global patterns in urban green space are strongly linked to human development and population density
Urban green space is important for alleviating high temperatures, pollution, and flooding in cities. Furthermore, it is becoming increasingly clear that urban green space is important for the mental and physical health of humans residing in cities and that urban green space may harbor unique biodiversity. Understanding the extent and drivers of urban green space is thus important. While urban green space has been mapped and studied at local to national scales, the global patterns and drivers of urban green space remain unknown, potentially hampering effective planning and allocation of resources toward reaching sustainable development goals. Here, we quantified the effect of environmental and socio-economic drivers (temperature, precipitation, human development, and population density) on urban green space globally by focusing on national capital cities. We used satellite imagery to map urban green space using two measures: the Normalized Difference Vegetation Index (NDVI), and the fractional cover of “green” land cover classes. NDVI is useful as it includes all vegetated surfaces, also small ones like gardens. However, land cover classes allow the exclusion of certain classes such as sports fields or cropland. We used boosted regression trees to show that climatic variables accounted for 75 % of the relative influence in urban green space, with a positive effect of precipitation and a negative effect of temperature. Importantly, socioeconomic variables accounted for 25 % of the influence on global urban green space, with a positive effect of human development index (HDI) and a negative effect of population density. HDI in relation to urban green space has not previously been tested globally, and our study shows that significantly affects urban greenspace. The results demonstrate that cities where development status is low and population densities are high, typically in the Global South, have less urban green space than the climate would predict. The results therefore suggest that human wellbeing does not only benefit directly from increasing human development and decreasing population densities in urban areas, but that these effects may be compounded by also improving nature’s contribution to people. 相似文献
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[目的]探究珠三角植被覆盖度空间分布和时空变化的驱动力,为该地区生态环境的保护提供科学参考。[方法]基于Landsat 5 TM和Landsat 8 OLI数据,利用像元二分模型反演珠三角2000,2005,2010,2015和2020年5个时期的植被覆盖度,分析珠三角植被覆盖度的空间格局和时空变化的过程。并结合5个时期的年降水量、年均温度、人口密度和土地利用,采用相关系数和地理探测器等方法开展研究。[结果](1)珠三角植被覆盖度在空间上表现为中部较低,边缘区域较高的分布格局,在佛山市、中山市、珠海市、广州市西南部、东莞市和深圳市较低,肇庆市、江门市和惠州市较高。植被覆盖度总体上表现为改善的趋势,改善的面积比例为64.99%,在时间上存在阶段性的差异,2010—2015年期间高植被覆盖度(80%以上)增长的面积最明显;(2)影响因素对植被覆盖度的驱动有明显的区域差异性,年降水量和土地利用程度起抑制作用的面积大于起促进作用的面积,年均温度和人口密度起促进作用的面积大于起抑制作用的面积;(3)植被覆盖度空间格局因子探测表明土地利用程度的解释力最强,交互探测表明年均温度与土地利用程度交互作用... 相似文献
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沈美萍 《农业图书情报学刊》2007,19(7):29-30
通过阐明Google相关模块的功能和数字图书馆情形下参考咨询工作的特点,提出参考咨询工作在面临Google挑战情况下的对策。 相似文献