Npswarn is the threshold that is used to signal the processes when space is getting low.
Npswarn是当空间变得较低时用于通知进程的阈值。
2
Infrared radiation heats up the pit membrane tissue, and TRPA1 channels open when a threshold temperature is reached, allowing ions to flow into the nerve cells and triggering an electrical signal.
红外线使窝器膜组织升温，当达到阈值后TRPA 1通路打开，离子流入神经细胞并催发电信号。
3
In this sense threshold means a sort of transition point like the threshold when an FM radio signal breaks through from being just static to being music (or maybe an AD).