Zhang Yuqi conducts a ultrasound check on a bullet train at a maintenance center in Guiyang, capital of southwest China's Guizhou Province, Jan. 30, 2019. As a model train hobbyist, 27-year-old Zhang Yuqi has made and collected more than a hundred model trains. Zhang is also a bullet train mechanic responsible for checking bullet trains during the Spring Festival travel rush at a maintenance center in Guiyang of Guizhou Province. Despite heavy work load and work pressure, Zhang said he is dedicated to ensuring the safety of bullet trains. (Xinhua/Ou Dongqu)