Technicians monitor data on a high-speed train during a joint test of Xi'an-Chengdu Passenger Railway in northwest China's Shaanxi Province, June 20, 2017. The Xi'an-Chengdu Passenger Railway, the first high-speed railway travelling through the Qinling Mountains with projected speed of 250 kilometers per hour, will undergo a joint test since Tuesday in its Shaanxi section. (Xinhua/Li Yibo)
