On November 2, 2014, "test instrument training class of China Railway No.4 Engineering Group Co., Ltd." was held in Chenxin company. China Railway fourth Bureau (Group) Co., Ltd. and the directors of laboratories of subordinate companies came to our company for training. Ruan Weixin, chairman of our company, Ruan Haixiang, general manager, Xu Feng, technical department and other leaders participated in the interactive exchange.