Optimized Matching Lift Unit Transmission Ratio of Engine Driven Ducted FanSenlin Xiao, Hongxin Qiao, Guanxiong Xu, Guailin Luo, Chao Ma, Zhiyong Guo and Depeng ZhangMATEC Web of Conferences, 166 (2018) 04003DOI: https://doi.org/10.1051/matecconf/201816604003