As for cost,Dr.Miller says patients with a heart pump spend less time in a hospital and have lower hospital costs than patients with severe heart disease.

VOA: standard.2010.01.27

That example I gave last time with the bicycle pump was not quite the right example.

上次我举打气筒的例子,是不太恰当的。

麻省理工公开课 - 热力学与动力学课程节选

You're taking the air inside of the pump and you're compressing it. You're doing it so fast that there's not enough time for heat to come out of the gas that's inside the pump towards the walls of the pump.

你把空气吸进气筒里并且压缩它,你的动作很快以至于,没有足够的时间让热量,从气筒里面跑出来,传递到气筒壁上。

麻省理工公开课 - 热力学与动力学课程节选

But this time this really is the bicycle pump.

但在这里是很符合实际的。

麻省理工公开课 - 热力学与动力学课程节选