https://zhuanlan.zhihu.com/p/33075914
http://blog.csdn.net/u011995719/article/details/79135818
https://blog.ddlee.cn/2018/01/18/%E8%AE%BA%E6%96%87%E7%AC%94%E8%AE%B0-Inverted-Residuals-and-Linear-Bottlenecks-Mobile-Networks-for-Classification-Detection-and-Segmentation/
https://www.zhihu.com/question/265709710