In the same measuring point, the reduction effect to the noise with high frequency was significant near by the surface.

同一测点，不同高度时，近地面处高频交通噪声减弱效果明显；

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In the same measuring point, the reduction effect to the noise with high frequency was significant near by the surface.

同一测点，不同高度时，近地面处高频交通噪声减弱效果明显；

youdao