Theoretical calculation in this paper is useful for the design of the air button battery.

本文中提供理论计算方法对扣式空气电池的设计具有实用意义。

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Plus, for last minute trips like New Years, what could be easier than pushing one button for air, hotels and transfers instead of trying to line them up individually?

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Therefore you're focused on just the most basic movements -- a common one involves jumping in the air, tapping the other button for the downward kick, and then tapping it again to fly backwards.

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To make selections in some parts of the menu, you simply push your hand forward in the air, like pushing an imaginary button.

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