他们的方法是按下上升键，让电梯升到顶层，然后一路坐到底层。
Their solution is to press the up-button, ride to the top, and then go down all the way down to the ground.
在没有持续上升的键上定义的索引自然会随时间变化变得比较混乱。
Indexes defined on keys that are not continuously ascending will naturally become less well-organized over time.
第一类利用变频器操作面板进行频率设置，只需操作面板上的上升、下降键，就可以实现频率的设定。
The first use of the frequency converter operating panel Settings, only the operation panel on the rise, drop key, you can achieve the frequency Settings.
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