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991.
Jim H. Chandler Tom Buffin-Bélanger Steve Rice Ian Reid David J. Graham 《The Photogrammetric Record》2003,18(103):209-223
Digital photogrammetry has been used to develop and test an artificial river bed moulding and casting system, which allows the pebbles within a coarse-grain river bed to be recreated for hydraulic research in a laboratory flow channel or flume. Imagery of both the original streambed and the cast facsimile was acquired using a non-metric Kodak DCS460 digital camera and digital elevation models and orthophotographs were derived and compared to assess the accuracy of the moulding and casting system. These comparative tests proved to be critical in modifying and developing the system.
Additional imagery was obtained in the field using a non-metric Olympus C3030 'compact' digital camera to assess whether far cheaper camera technology could deliver data appropriate for such comparative examinations. Internal calibration parameter sets and data that were generated were compared with data obtained by the non-metric Kodak DCS460. These tests demonstrate that digital sensors built around high-quality 35 mm professional camera bodies and lenses are required for comparative examinations and for similar system development. 相似文献
Additional imagery was obtained in the field using a non-metric Olympus C3030 'compact' digital camera to assess whether far cheaper camera technology could deliver data appropriate for such comparative examinations. Internal calibration parameter sets and data that were generated were compared with data obtained by the non-metric Kodak DCS460. These tests demonstrate that digital sensors built around high-quality 35 mm professional camera bodies and lenses are required for comparative examinations and for similar system development. 相似文献
992.
Akira Hirano Roy Welch Harold Lang 《ISPRS Journal of Photogrammetry and Remote Sensing》2003,57(5-6):356
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on-board the National Aeronautics and Space Administration's (NASA's) Terra spacecraft provides along-track digital stereo image data at 15-m resolution. As part of ASTER digital elevation model (DEM) accuracy evaluation efforts by the US/Japan ASTER Science Team, stereo image data for four study sites around the world have been employed to validate prelaunch estimates of heighting accuracy. Automated stereocorrelation procedures were implemented using the Desktop Mapping System (DMS) software on a personal computer to derive DEMs with 30- to 150-m postings. Results indicate that a root-mean-square error (RMSE) in elevation between ±7 and ±15 m can be achieved with ASTER stereo image data of good quality. An evaluation of an ASTER DEM data product produced at the US Geological Survey (USGS) EROS Data Center (EDC) yielded an RMSE of ±8.6 m. Overall, the ability to extract elevations from ASTER stereopairs using stereocorrelation techniques meets expectations. 相似文献
993.
利用重力场模型和局部重力资料计算GPS水准高的精度探讨 总被引:2,自引:0,他引:2
利用大地水准面高,结合GPS测量的高程信息,直接计算GPS水准高,是一种全新诱人的解决方案。本文就这种方案,根据其核心技术-大地水面高的性质:长波长-全球重力场;中波长-局部重力资料,短波长-数据地形,对它的具体实现,适用范围以及精度分析作了详尽的探讨,在此基础上,提出一些GPS水准应用规范和要求,并利用实验数据对其进行验证。 相似文献
994.
995.
996.
基于参考面的可视域算法 总被引:2,自引:0,他引:2
与传统基于视线的可视域算法相比,该算法不需进行DEM内插,无冗余计算,计算时间和视点位置与可视域面积无关,受DEM区域影响不大。 相似文献
997.
This paper describes work undertaken to measure deformation of a pavement within the Newcastle University Rolling Load Facility (NUROLF). Precise three dimensional measurements of the pavement have been produced from stereo-imagery taken with diVerent cameras, using both analytical and digital photogrammetric instrumentation. The photogrammetric measurements, and those from the existing system consisting of an array of linear voltage displacement transducers, have been compared with measurements produced using a digital level. Encouraging results have been achieved and photogrammetry has been shown to be capable of producing a similar accuracy to the existing system. There are many advantages associated with a photogrammetric survey but attempts to establish a permanent, automated photogrammetric system for the rolling load facility at a reasonable cost have so far been unsuccessful. It is anticipated that, with the falling cost of high resolution digital sensors, such a system will soon be possible. 相似文献
998.
VR技术中地形场景的实时显示 总被引:2,自引:0,他引:2
地形场景的建模及 3维重现在虚拟现实中占据重要的地位。文中借鉴了国内外多分辨率 3维模型建模方面的相关成果 ,实现了对多分辨率地形模型的实时显示 相似文献
999.
利用干涉合成孔径雷达技术提取数字地面模型 总被引:6,自引:1,他引:6
简单介绍了干涉测量合成孔径雷达((INSAR,InterferometricSyntheticApertureRadar;简称:干涉雷达)的技术特点及原理,概述了干涉图像的相位解缠算法,并以西藏玛尼地区ERS-1/2SAR图像为例,提取了数字高程模型(DEM). 相似文献
1000.
基于小波分析的地貌多尺度表达与自动综合 总被引:28,自引:5,他引:28
基于小波多分辨率分析原理,给出了一种尺度依赖的地表形态抽象与表达方法。基于该方法研究了多尺度的地貌自动综合,提出了利用小波系数的范数比作衡量相应尺度综合程度的数量化指标,并结合实例予以说明。 相似文献