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水面的有效性识别和纠正基于快速里埃变换的时空图像速度测量 (FFT-STIV) 结果

Zhen Zhang^1,2, Lin Chen¹, Zhang Yuan¹

¹College of Information Science and Engineering, Hohai University, Changzhou 213200, China.

Sensors (Basel, Switzerland)

|January 11, 2025

概括

本研究引入了一种新的方法,通过识别和纠正错误来提高基于快里叶变换的时空图像速度测量 (FFT-STIV) 精度. 该技术在复杂的环境中显著减少了错误,提高了水文速度测量.

科学领域:

水文学的水文学
流体动力学流体动力学
图像处理图像处理

背景情况:

基于快里叶变换的时空图像速度测量 (FFT-STIV) 是测量水速的宝贵工具.
然而,由于错误检测和盲区,FT-STIV在复杂的环境中可能会产生重大错误.

研究的目的:

开发和验证一种方法来识别和纠正FT-STIV结果中的严重错误.
提高水文速度测量的准确性和可靠性.

主要方法:

引入了三个评估指标:对称性,SNR和光谱宽度,以过无效的FFT-STIV结果.
使用不同的数据集为这些指标建立了值,消除了错误的速度,同时保留了有效的速度 (99.83%).
结合有效的速度与截面速度分布规律,以适应速度曲线并纠正无效和盲区速度.

主要成果:

提出的方法有效地识别和纠正了FFT-STIV在各种条件 (水位,天气,照明) 的结果.
在150米内实现了不到8.832%的平均相对误差 (MRE),超过了标准的FFT-STIV.
在许多无效的性传播疾病中,在夜间表现优异,在纠正后产生4.383%的MRE,超过了手动标签.

结论:

开发的方法显著提高了FFT-STIV用于水文速度测量的准确性和可靠性.
它有效地解决了FFT-STIV在复杂环境和具有挑战性的条件中的局限性.
该技术为各种水文应用中准确的速度分析提供了强大的解决方案.

关键词:

金融金融公司 (FFT)史蒂夫斯蒂夫斯蒂夫斯蒂夫斯蒂夫是什么意思河流表面的速度河流表面的速度有效性识别标识的有效性速度纠正速度的纠正

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