共查询到17条相似文献，搜索用时 109 毫秒
1.
2.
3.
在保证海岸带区域控制点均匀分布的基础上，对3景SPOT-5影像分别使用1：5万DEM和SRTM90m数据，开展6个、9个、12个控制点的影像正射校正。结果表明：在海岸带区域，基于传感器物理模型的1景SPOT-5影像正射校正，6个控制点即可保证较高的精度，控制点数量的增多对精度的提高并不显著；1：5万DEM比SRTM90m数据对影像的正射校正精度略高，但并不明显，在缺少1：5万DEM时，用SRTM90m数据代替亦能满足908课题的精度要求，进一步验证了SRTM90m数据在高分辨率遥感影像正射校正中的可用性。 相似文献
4.
5.
数字高程模型（DEM）是描述地表起伏形态特征的空间数据模型。DEM完全可以代替传统使用等高线对地形表面的描述，进而满足对等高线数据相同的各种需求。内插是DEM的核心问题，它是DEM各种应用的基础。介绍了加权最小二乘曲面拟合法构建规则格网DEM的理论和方法。试验结果表明：加权最小二乘曲面拟合算法具有插值结果较精确、处理效率较高和模拟地表效果较好等优点。 相似文献
6.
在保证海岸带区域控制点均匀分布的基础上,对3景SPOT-5影像分别使用1:5万DEM和SRTM90m数据,开展6个、9个、12个控制点的影像正射校正.结果表明:在海岸带区域,基于传感器物理模型的1景SPOT-5影像正射校正,6个控制点即可保证较高的精度,控制点数量的增多对精度的提高并不显著;1:5万DEM比SRTM90m数据对影像的正射校正精度略高,但并不明显,在缺少1:5万DEM时,用SRTM90m数据代替亦能满足908课题的精度要求,进一步验证了SRTM90m数据在高分辨率遥感影像正射校正中的可用性. 相似文献
7.
8.
9.
10.
提出基于遥感的影像图和DEM影像图,进行海图地形和DEM等高线数据数字化提取并将提取结果导出到其他GIS系统中的新技术方法。该技术处理速度快,生成的影像图和提取地形数据具有精度高(可达到1 m)的特点。这项新的处理技术可达到提高实际测绘中的劳动效率,降低外业测量人员的野外工作强度,及时更新地理信息、简便地校验测量的质量精度和节省作业经费的目的。 相似文献
11.
A change in the elevation of bare tidal flats outside a mangrove area is an indispensable factor for the sustainable development of mangroves. Waterline extraction, as an effective and economical tool used in reconstructing the terrain of an intertidal zone, has been widely applied to open-coast tidal flats by constructing a digital elevation model (DEM). However, mangrove wetlands are usually located in wave-sheltered sites, such as estuaries and bays that have narrow tidal channels flanked by tidal flats. Changes in water level are affected by the dry-wet processes of complex landforms caused by tides. This article takes as a study case the area of Yingluo Bay, which covers the core region of the Zhanjiang and Shankou National Mangrove National Nature Reserve in southwestern China. Waterline extraction based on seventeen multisource and multispectral satellite images obtained from December 2014 to April 2015, combining the finite-volume coastal ocean model (FVCOM) hydrodynamic model in an iterative process, was used to generate a topographical map of the bare tidal flat outside the mangrove area in Yingluo Bay. The quality of the iterative DEMs was evaluated via six transects of a ground-based survey using Real - time kinematic (RKT) GPS in May 2015. The mean absolute error (MAE) and root mean square error (RMSE) of the DEM decreased with an increase in the number of iterations. In this study, the DEM in the third iteration was used as the final output because the difference from the previous iterative DEM satisfied an inversion-stopping criterion. The MAE and RMSE of the final DEM with the measured data were 0.072 and 0.09?m, respectively, without considering small tidal creeks. The method used in this study can be an effective and highly precise approach for detecting and reconstructing the historical terrain of a bare tidal flat outside a mangrove area. This work also has great importance regarding intertidal resource management and the sustainable development of mangroves facing the vulnerable coastal ecological environment. 相似文献
12.
13.
平缓潮滩的测绘受到潮汐和淤泥的双重影响,难以进行大区域的人工作业。探讨利用序列遥感影像构建潮滩DEM的技术方法。基于多时相BJ-1小卫星自动提取水边线,利用中国近海高分辨率潮位网格,与卫星过境时刻的水边线进行空间关联与内插,生成带有高程值的系列水边点,并以此来构建潮滩地形三角网,最后生成格网潮滩DEM。与现场RTK验证的三个剖面的高程相比,其高程绝对误差均值小于0.2m。结果表明,应用中分辨率遥感影像进行淤泥质潮滩地形反演可以达到一定比例尺的制图精度。 相似文献
14.
15.
数字摄影测量技术应用于海岸带地形测量成为一种趋势,在分析现有海、陆图生产技术体系和海岸地形图表示内容特点的基础上,提出了利用一体化测图技术进行海岸带地形数据生产的新思路.针对任务调度、立体采集、外业调绘、入库和制图编辑以及质量控制等海岸带地形数据生产的关键工序,进行了一体化测图技术实现的探讨. 相似文献
16.
Avidesh Seenath 《Marine Geodesy》2013,36(6):581-604
AbstractThis article examines whether Digital Elevation Model (DEM) resolution affects the accuracy of predicted coastal inundation extent using LISFLOOD-FP, with application to a sandy coastline in New Jersey. DEMs with resolution ranging from 10 to 100 m were created using coastal elevation data from NOAA, using the North American Vertical Datum of 1988. A two-dimensional hydrodynamic flood model was developed in LISFLOOD-FP using each DEM, all of which were calibrated and validated against an observed 24-h tidal cycle and used to simulate a 1.5 m storm surge. While differences in predicted inundated area from all models were within 1.0%, model performance and computational time worsened and decreased with coarser DEM resolution, respectively. This implied that using a structured grid model for modeling coastal flood vulnerability is based on two trade-offs: high DEM resolution coupled with computational intensity, but higher precision in model predictions, and vice versa. Furthermore, water depth predictions from all DEMs were consistent. Using an integrated numerical modeling and GIS approach, a two-scale modeling strategy, where a coarse DEM is used to predict water levels for projection onto a fine DEM was found to be an effective, and computationally efficient approach for obtaining reliable estimates of coastal inundation extent. 相似文献