相关实验视频
Updated: Sep 15, 2025

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使用B-splines对基于点云的几何表面表示的方差成分估计
Elisabeth Ötsch1, Corinna Harmening2, Hans Neuner1
1Research Group Engineering Geodesy, Geodesy and Geoinformation, TU Vienna, Vienna, Austria.
概括
本研究使用差异成分估计 (VCE) 来分离测量和模型不确定性在几何表面近似. 当模型不确定性超过测量不确定性时,可以实现现实的分离.
科学领域:
- 地质测量是指地质测量.
- 计算几何学的计算几何学
- 统计建模 统计建模
背景情况:
- 评估时代间位移严重依赖于点云对几何表面表示的随机信息.
- 点云的不确定性可能来自仪表,环境或对象特定的因素,以及近似方法的模型不确定性.
研究的目的:
- 通过差异成分估计 (VCE) 调查测量和模型不确定性的现实估计和分离.
- 评估VCE在区分测量 (距离,角度) 和模型不确定性 (共变函数) 之间的有效性.
主要方法:
- 使用 BIQUE 估计方法对张量积 B-spline 表面近似进行差异成分估计 (VCE).
- 创建了一个更复杂的B-spline表面,通过人工改变点来模拟模型不确定性.
- 与测量和模型不确定性相关的分离的重叠方差元件.
主要成果:
- 发现差异组件在特定条件下是可分离和可估计的.
- 当模型不确定性超过测量不确定性时,分离成功发生.
- 在变异共变矩阵 (VCM) 设置中,仅包括受模型偏差影响的点至关重要.
结论:
- 在几何点云近似中,VCE是解开测量和模型不确定性的可行方法.
- 这项研究表明了不确定性和数据选择的相对大小对于准确的VCE的重要性.
- 这些发现有助于更可靠地评估随时间变化的表面变化.
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