带C-scattered空间因子的积空间的覆盖性质

通过给出正则次中紧C-scattered空间的一个紧式θ-开覆盖序列,证明了带C-scattered空间因子的积空间的中紧性和次中紧性的两个定理.

A Note about σ-locally Finite PF-regular Closed Net

If X = U{Xn: N} is a regular space, Xn has aσ-locally finite PF-regular closed net, and Xn is a closed subset of X for each n N, then X has a σ-locally finite PP-regular closed net;