1. Department of Mechanical and Electrical Engineering, Shijiazhuang University of Applied Technology, Shijiazhuang 050081, China
2. Railway Locomotive & Car Department, Hebei Vocational College of Rail Transportation, Shijiazhuang 050022, China (Corresponding author), e-mail: jingll0321@163.com, https://orcid.org/0000-0002-6720-4222