Firstly, the power spectral density function of refractive index is given including the effects of inner and outer scale of the turbulence.

首先，给出了包含大气湍流内，外尺度效应的折射率功率谱密度函数。

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Using power spectral analysis, centennial and millennial-scale cycles of Paleo-monsoon were extracted. In the cycles, 71 a is the basic cycle of East Asian Monsoon.

应用功率谱分析的方法，提取出同时段百年尺度和千年尺度的古季风周期，其中71 a周期为本文首次提出，并被认为是东亚季风活动最显著的基准周期之一。

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Firstly, texture and shape features are extracted at the pixel level, and spectral features are extracted at the object level based on multi-scale image segmentation maps.

首先在画素级上提取影像的纹理和形状结构特征，在构建的多尺度分割集影像上提取物件的区域光谱特征。

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