A staff member analyzes structure of captive balloon at the 38th Research Institute of China Electronics Technology Group Corporation in Hefei, capital of east China's Anhui Province, March 28, 2017. The captive balloon is an air platform carrying various devices, such as warning radar, video surveillance equipment, fog detection devices, communication relay devices and imaging equipment. The balloon is expected to play a role in precaution and detection, environmental surveillance, security and protection monitoring. (Xinhua/Cheng Tingting)
