The Grounding of electric devices is a kind of normal ways for restraining noise and interfere.

电器通过接地抑制噪声和防止干扰是常用的一种方法。

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Safety experts estimate that the restraining devices save more than four thousand lives a year in the United States alone.

VOA: special.2010.02.09

In my experience, this has sometimes involved the assistance of one or more accomplices or the use of physical controls such as a remote location, soundproof room, underground chamber or elaborate restraining devices.

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