不是所有光滑流都有横截面，一个明显的必要条件是流不能有奇点。横截面是由庞加莱 (Poincare,(J.-)H) 引进的。通过横截面可以建立光滑流与微分同胚生成离散动力系统之间的联系。
横截面 [héng jié miàn]
网络释义专业释义
双语例句原声例句
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我们把它理解为一个横截面的序列，而不是随着时间有机地变化的东西。
We understand it as a sequence of cross-sections rather than something that somehow organically changes through time.
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在地球上，人们认为，表明太阳黑子周期最可靠的迹象之一是树木的生长速度，就像树干横截面上可见的年轮一样。
On Earth, among the surest indications of sunspot cycles are believed to be the rate that trees grow, as seen in the rings visible in the cross sections of their trunks.
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别里耶夫选择了悬臂式上单翼和双阶船身的结构，后者具有较大的横截面。
Beriev chose a scheme of the single-cantilever monoplane with two-step boat, which had a large cross-deadrise.
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In that case, we understand it as a sequence of cross-sections rather than something that somehow organically changes through time.
这样，我们就是在学习一个个语言的横截面,而不是语言自然的变化过程。
应用推荐
$firstVoiceSent
- 来自原声例句