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美国三维坐标基准现代化新进展
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作者 许炜 吕志平 +3 位作者 李林阳 邝英才 王方超 杨凯淳 《测绘通报》 CSCD 北大核心 2021年第8期61-64,92,共5页
随着空间大地测量技术的发展和对高精度参考系统的迫切需求,美国国家大地测量局(NGS)计划对美国国家空间参考系(NSRS)进行现代化。本文主要介绍了提出并采用板块固定参考框架的理由,并根据NGS的NSRS现代化蓝图阐述了三维坐标基准现代化... 随着空间大地测量技术的发展和对高精度参考系统的迫切需求,美国国家大地测量局(NGS)计划对美国国家空间参考系(NSRS)进行现代化。本文主要介绍了提出并采用板块固定参考框架的理由,并根据NGS的NSRS现代化蓝图阐述了三维坐标基准现代化的基本策略及特点。新的三维坐标基准相比现有的NAD83,主要改进为:(1)采用了"板块固定"策略,板块参考框架由3个增加至4个;(2)参考框架实现将主要依靠主动控制点(连续运行基准站),被动控制点仅充当补充和辅助角色;(3)将提供框架内速度场模型。目前各板块框架板块旋转的欧拉极点和框架内速度场模型还需进一步确定。 展开更多
关键词 美国国家空间参考系现代化 三维坐标基准 板块固定 连续运行基准站 框架内速度场模型
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INTERVAL FINITE VOLUME METHOD FOR UNCERTAINTY SIMULATION OF TWO-DIMENSIONAL RIVER WATER QUALITY 被引量:2
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作者 HELi ZENGGuang-ming] +1 位作者 HUANGGuo-he LUHong-wei 《Journal of Hydrodynamics》 SCIE EI CSCD 2004年第4期455-463,共9页
Under the interval uncertainties, by incorporating the discretization form offinite volume method and interval algebra theory, an Interval Finite Volume Method (IF-VM) wasdeveloped to solve water quality simulation is... Under the interval uncertainties, by incorporating the discretization form offinite volume method and interval algebra theory, an Interval Finite Volume Method (IF-VM) wasdeveloped to solve water quality simulation issues for two-dimensional river when lacking effectivedata of flow velocity and flow quantity. The IFVM was practically applied to a segment of theXiangjiang River because the Project of Hunan Inland Waterway Multipurpose must be started workingafter the environmental impact assessment for it. The simulation results suggest that there existrather apparent pollution zones of BOD_5 downstream the Dongqiaogang discharger and that of CODdownstream Xiaoxiangjie discharger, but the pollution sources have no impact on the safety of thethree water plants located in this river segment. Although the developed IFVM is to be perfected, itis still a powerful tool under interval uncertainties for water environmental impact assessment,risk analysis, and water quality planning, etc. besides water quality simulation studied in thispaper. 展开更多
关键词 interval finite volume method (ifvm) uncertainty simulation water quality
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