The simulation result proves: Used this converter's topology structure, the envelope curve of import electric current follows entering voltage change. And power factor correction has been realized.

仿真分析结果证明：该变换器拓扑结构能够使输入电流的包络随着收入电压变化，有效的实现了功率因数校正。

youdao

The primary question is the energy saving in envelope. Solar heat gain of Windows is an important factor that influences the energy consumption of air conditioning in buildings.

建筑节能面临的首要问题是建筑围护结构的节能，而窗的太阳得热量是影响建筑空调能耗的一个非常重要的因素。

youdao

In fact, the envelope is identical in each case except for a scale factor.

事实上，在这几种情况下，除差一个倍率外，包络是是完全相同的。

youdao

After extensive research, the fire service decided that condoms - rather than pens, rulers, etc - packaged in a cardboard envelope bearing the core message, had the best novelty factor and the ability to communicate a wider safety message.

BBC: Fire service condoms for students