It does this by fitting small piezoelectric acoustic sensors to parts of the structure to detect the particular frequency of noise caused by a crack in aircraft-grade aluminium.

把小型压电声传感器安装到这种构造部位上，检测由航空级铝材裂纹所致的特定频率的噪音，靠这样就能监测飞机裂纹。

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Noise map is produced from fitting image of superposition of noise levels of road traffic, railway, aircraft and industry at each reception point.

噪声地图是由道路交通噪声、铁路噪声、工业噪声和机场噪声等对城市地图上每个接收点的叠加噪声值拟合图像绘制而成。

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As well as the new aircraft, it is expanding its navy's capabilities, re-fitting older Russian aircraft carriers as well as building new ones.

包括新的航空母舰，它大大的扩展了他的海军水平。他正在翻修俄国的航母，同时自己也在造新的。

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