net change

基本解释

Rather than simply providing the net change over a period, this approach discloses the components that make up the change.
而不是简单地计算一个时间段的净变化，这种方法揭示了引起变化的各个要素。
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If you are measuring volatility as the gross amount of change over time in LOCs, then you will want to measure volume as the net change over time in LOCs as well.
如果您根据 LOC 中的随时间变更的总量度量易变率，那么您会希望也根据 LOC 中随时间的净变更度量容积。
Whereas chemical rockets waste too much propellant to reach a net change in spacecraft velocity, electric thrusters can do exactly the same mission using just a small fraction of the propellant.
鉴于化学燃料火箭浪费太多的推进剂难以实现飞船速度的静变化，电力推进器仅仅使用一小点推进剂就可以做同样的任务。

Once the gases are mixed, there's not going to be any further net change in the system.
一旦气体混合,这个系统就不会发生任何净的变化。
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Now the last thing is that because the neutron has no net charge, we can change neutron number.
现在，最后一件事是,因为中子没有净电子，我们可以改变中子数。
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But it would result in no net change in tax revenues (at least as Romney measures it).
FORBES: How Will Romney Pay For Tax Cuts? Wouldn't You Like To Know.
They cut exposure overall, but did so by cutting 4, 191 gross longs and slicing 3, 927 gross shorts, which made the net change modest.
FORBES: FOCUS: Speculators Cut Bullish Gold, Silver Positions -- CFTC