Visitors look at a greenhouse system based on the Internet of Things (IoT) at the 25th China Yangling Agricultural Hi-Tech Fair in Yangling, northwest China's Shaanxi Province, Nov. 5, 2018. The 25th China Yangling Agricultural Hi-Tech Fair kicked off here on Monday. The event features more than 60 activities which involve international cooperation on agricultural technology, rural industrial integration, as well as agricultural innovation and promotion. (Xinhua/Shao Rui)