Qiao Sukai operates the facilities during the fuel assemblies replacement at the Dayawan Nuclear Power Plant in Shenzhen, south China's Guangdong Province, April 12, 2019. Every 18 months, the Dayawan Nuclear Power Plant has to undergo a fuel assemblies replacement, which is one of the most important moments for the nuclear power plant. Dozens of engineers are divided into four shifts and operate the equipment day and night when the reactor is shut down. Their leader, Qiao Sukai, has been dealing with nuclear fuel since July 1993 when the nuclear fuel assembly of Dayawan Nuclear Power Plant arrived. The professional and technical maintenance team led by Qiao is responsible for the maintenance of nuclear fuel for more than half of the nuclear power units in the country. Qiao and his team have successfully operated fuel installing and uninstalling more than 170 times without making a single mistake. (Xinhua/Mao Siqian)