inaudibility

Infrasound existing widely in nature has already aroused the interests of environmental and military scientists in many countries for its characters of less attenuation during propagation, inaudibility and broad harm in some cases.

次声广泛存在于自然界中，由于其在传播时不易衰减，不能被听到等特点，在一定作用条件下，可造成危害，已引起一些国家的环境科学家和军事科学家的关注。

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The experimental results show that the algorithms are blind, and they have beautiful robustness, sensitivity and inaudibility.

仿真实验表明，本文的水印算法具有很好的鲁棒性、脆弱性和不可感知性，并且实现了水印的盲提取。

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