in august 1958 , the ministry of defense appointed zhang yunyu -lsb- 1728 5686 6877 -rsb- to be director of the nuclear test team -lrb- later the title was changed to nuclear test base commander -rrb- , chang yong -lsb- 1603 0516 -rsb- to head the political committee , and zhang zhishan -lsb- 1728 1807 0810 -rsb- to be deputy director -lrb- later changed to deputy commander of the nuclear test base -rrb- .