With NIR spectra, the analytical information is contained in small spectral variations and usually dominated by the features such as light scattering, background noise and baseline drift.

近红外光谱不但包含着物质成分信息，而且这些信息完全掩盖在众多复杂背景当中（包括光散射、背景噪声以及背景漂移）。

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But SAR image is liable to be affected by speckle noise, while almost spectral image have shortcomings of low contrast between object and background, edge blurring.

但SAR图像容易受到相干斑噪声的影响，而光谱图像普遍存在目标与背景对比度差、边缘模糊的缺点。

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In this paper the speech enhancement method based on fuzzy system is discussed in strong background noise, and a comparison is made between this method and the spectral subtraction algorithm.

讨论强背景噪声下的基于模糊系统的语音增强方法，并与减谱法语音增强算法进行比较。

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