排序方式： 共有144条查询结果，搜索用时 0 毫秒
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Google Earth在森林防火信息管理中的实现方法 总被引：1，自引：0，他引：1
为了提高森林防火信息管理中空间数据的利用效率,针对Google Earth的共享遥感影像数据,提出利用Google Earth的二次开发,将其应用到森林防火信息管理。笔者通过调用Google Earth类库的方法,开发实现了森林防火信息系统。系统读取Access数据库的坐标信息,自动生成并加载各类地标文件,实现防火专题信息定位、GPS跟踪、历史火场位置重现等功能,为森林防火管理与决策提供依据。 相似文献
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农产品快速图形化追溯系统构建 总被引：5，自引：4，他引：1
农产品快速图形化溯源是保障追溯过程可信度、增强追溯结果显示度、提高公众参与度的重要措施。该文以基于地理坐标和多重加密的农产品追溯码为编码方式,以Google Earth地图为展示工具,设计了以“正确性判断-追溯码解析-产地定位-属性追溯-结果显示”为主线的追溯流程;通过调用Google Maps API,采用.Net平台构建了基于B/S架构的农产品快速图形化溯源系统。系统通过在广州市农产品质量安全监管平台的使用表明,系统在满足一般属性追溯的同时,可快速定位到产地并以地图的形式展示,体现了溯源图形化、应急定位快速化的特点,有利于追溯系统的推广应用和质量安全突发事件的应急管理。 相似文献
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为在土壤分析研究时,制定工作量少、试验设计经济合理,同时采样点具备代表性的野外采样方案,采用GPS与Google Earth相结合的方法,在陕西省泾惠渠灌区研究了土壤水力参数区域尺度的空间变异性,结果表明:土壤饱和含水率与饱和导水率在该区域尺度下属于中等变异,且两者均具有较强的空间依赖性;饱和含水率的最佳拟合模型为球形模型,土壤饱和导水率的最佳拟合模型为指数型;推荐两者的采样间距分别为2.38 km和7.14 km。 相似文献
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Aleksandr KAVETSKIY Galina YAKUBOVA Nikolay SARGSYAN Clyde WIKLE Stephen A. PRIOR Henry Allen TORBERT Bryan A. CHIN 《土壤圈》2019,29(3):334-343
Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A Global Positioning System(GPS) device and softwares required to simultaneously acquire gamma signals and geographical positions during scanning operations were added to an existing measurement system. The reliability of soil carbon measurements in scanning mode was demonstrated to be in agreement with results acquired from static mode. The error analysis indicated that scanning measurements can be conducted with the same accuracy as static measurements in approximately one fourth the time. To obtain results suitable for mapping analogous to traditional chemical analyses(i.e., ± 0.5 in weight percent or ± 0.5 w%), scanning time over a given site should be ca. 15 min using the current measurement system configuration. Based on this measurement time, a reasonable towing speed of 3–5 km h-1, the necessity for complete site coverage during scanning, the number of sites(within the surveyed field), and the required total measurement time can be estimated. Soil carbon measurements for 28 field sites(total area ca. 2.5 ha) were conducted in ca. 8 h. Based on acquired data,a soil carbon distribution map was constructed utilizing various softwares. The surveyed field area included an asphalt road that had carbon readings higher than the surrounding land. The clarity with which these carbon-rich zones were delineated on the constructed map represents evidence supporting the veracity of this method. Neutron-gamma analysis technology can greatly facilitate timely construction of soil carbon maps. 相似文献
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There is a growing body of literature that shows internet search volume on a topic, such as fishing, is a viable measure of salience. Herein, internet search volume for ‘fishing’ and ‘angling’ is used as a measure of public interest in fishing, in particular, recreational fishing. An online tool, Google Insights for Search, which allows one to study internet search terms and their volume since 2004, is used to examine trends in interest in fishing for 50 countries. Trends in normalised fishing search volume, during 2004 through 2011, varied from a 72.6% decrease (Russian Federation) to a 133.7% increase (Hungary). Normalised fishing search volume declined in 40 (80%) of the countries studied. The decline has been relatively large in English‐speaking countries, but also has been large in Central and South American, and European countries. Analyses of search queries provide a low‐cost means of gaining insight into angler interests and, possibly, behaviour in countries around the world. 相似文献
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为加强大围山国家森林公园水土保持的研究与管理,在水土保持地理信息子系统、监测信息子系统、专家系统中引入了Google Earth,设计和构建了基于Google Earth的大围山水土保持信息系统。通过对该系统框架及应用方法和前景的阐述,并比较了该系统与其它相关信息系统的优势和不足,实现对大围山水土流失数据信息的高效存储和管理。研究表明:Google Earth在水土保持信息系统中具有重要的推广应用价值。 相似文献
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杨小琼 《农业图书情报学刊》2010,22(8):91-93,103
专业搜索引擎Google Scholar与Scirus较之综合性搜索引擎,具有重复率低、相关性好、准确率高的优点,成为目前使用率最高的两种专业搜索引擎。本文对两种专业搜索引擎作了简要的介绍,并分别从收录范围、检索功能、查询结果、检索结果排序等方面对两者作了对比分析,最后对两者的特点进行点评与展望。 相似文献
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为从作物轮作角度分析华南典型赤红壤农区耕地质量空间差异,针对华南典型赤红壤农区构建作物轮作系统遥感分类体系,基于空间分析、文献支持、野外实地调查、农户访谈与专家知识,建立不同作物轮作系统与耕地质量等级之间的关联关系;基于Sentinel-1与Sentinel-2时间序列遥感数据、利用决策树制图方法,开展作物轮作系统遥感制图,并在不同空间尺度分析耕地质量空间差异与规律。结果表明,作物轮作系统与耕地质量之间存在关联关系,总体而言,水田轮作系统由于化肥投入较低、对土壤干扰较小、长时间被水面覆盖,不易引起土壤酸化等耕地质量问题,耕地质量等级较高;蔬菜、果园系统由于化肥投入较高,耕地质量一般较低,具体表现为土壤酸化、土壤重金属污染等问题。研究区蔬菜轮作系统比例最高,其次为果园系统。研究区耕地质量总体一般,主要为三等地,呈现出明显的空间分异。本研究初步探明作物轮作与耕地质量的关联关系,并将作物轮作遥感制图结果应用于耕地质量空间差异研究,由于耕地质量特征较难直接通过遥感反演获取,通过监测地表作物种植情况进而反演耕地质量具有理论可行性,未来有必要深入解析作物轮作、地形地貌、气象水文等要素与耕地质量的关联关系,构建大数据驱动的耕地质量时空差异评估技术体系,支撑跨尺度耕地质量监测与评价研究。 相似文献
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通过比较两个搜索引擎类型特征、搜索功能、运用技巧等,阐述如何评价搜索引擎．如何使用不同类型搜索引擎快速准确查找所需信息。 相似文献