其中 Φ(x)是标准正态分布 CDF。
If you're an early adopter looking to try out AR glasses, it's hard to argue with the $299 price tag. For reference, Xreal recently launched a more affordable version of its glasses called the Xreal 1S, priced at $449.
，这一点在搜狗输入法下载中也有详细论述
全链路性能调优：实现成本下降 50%
A wall currently separates the Nant Clydach tributary from the street, but the environment body, Natural Resources Wales, said building a raised flood defence wall was "not economically viable".