They wer e all afr aid of a gr een mon key .

他们都害怕一只绿猴子。

How about three hours afr we left new york ?

我们离开纽约三个小时以后?

Model based afr control technology has become a hotspot in gasoline engine control research , especially during transient conditions afr could have a excursion because of manifold air flow and fuel film dynamics , so controlling of afr this time is very important .

基于模型的空燃比控制技术是当前国内外研究的热点。特别是在瞬态工况下由于受空气和油膜动态效应等的影响，空燃比会发生偏离，此时空燃比的精确控制尤为重要。