A data-driven early micro-leakage detection and localization approach of hydraulic systems CAI Bao-ping(蔡宝平) 1, 2 , YANG Chao(杨超) 1, 2 , LIU Yong-hong(刘永红) 1, 2 , KONG Xiang-di(孔祥地) 1, 2 , GAO Chun-tan(高春坦) 1, 2 , TANG An-bang(唐安邦) 1, 2 , LIU Zeng-kai(刘增凯) 1, 2 , JI Ren-jie(纪仁杰) 1,2