rarefaction

基本解释

This is called a rarefaction and is represented by widely spaced dots .
这个区域称为稀疏区，并用疏散的小点表示。
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Dam-break flood waves often vary rapidly or even discontinuously, with both rapid and tranquil flow behaviors, as well as both compression and rarefaction waves.
溃坝洪水波通常为迅变或间断流动，同时兼有急流和缓流、压缩波和稀疏波等流态。
It carefully investigates thought background of proposing zero measure set, thought process of proposing asymptotic measure and rarefaction of proposing zero measure set, and influences on M.
以法国数学家波莱尔的有关工作为核心，重点考察了他提出零测集的思想背景，提出零测集渐近测度和稀疏度的思想演变过程、思想方法及影响。