B-Surface is the surface of a component that you can't see in the normal service condition.

级表面是在正常使用状态下看不到的部件表面。

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Said method can solve acoustic radiation prediction after structure surface damping process with wide range application boundary condition which can not be realized by normal commercial software.

因而用本方法可用来解决结构表面阻尼处理后的声辐射预测问题，应用边界条件非常广泛。此功能是一般商用软件所不能实现的。

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In this, the stream of video and audio data is recorded as a series of minuscule spots on the disc's surface that have been gently fried by a laser beam and turned from their normal crystalline condition to an amorphous state that has different reflective properties.

ECONOMIST: Digital video discs