People attend an open day event at a grain depot of Sinograin in Guangzhou, capital of south China's Guangdong Province, Oct. 14, 2019. The event was held to demonstrate modern, high-tech and intelligent grain depots of China's state grain stockpiler Sinograin. (Xinhua/Huang Guobao)

　　Students from Guangdong Vocational Institute of Public Administration view high-quality corn during an open day event at a grain depot of Sinograin in Guangzhou, capital of south China's Guangdong Province, Oct. 14, 2019. The event was held to demonstrate modern, high-tech and intelligent grain depots of China's state grain stockpiler Sinograin. (Xinhua/Huang Guobao)

　　People attend an open day event at a grain depot of Sinograin in Guangzhou, capital of south China's Guangdong Province, Oct. 14, 2019. The event was held to demonstrate modern, high-tech and intelligent grain depots of China's state grain stockpiler Sinograin. (Xinhua/Huang Guobao)

　　Students from Guangdong Vocational Institute of Public Administration attend an open day event at a grain depot of Sinograin in Guangzhou, capital of south China's Guangdong Province, Oct. 14, 2019. The event was held to demonstrate modern, high-tech and intelligent grain depots of China's state grain stockpiler Sinograin. (Xinhua/Huang Guobao)

　　People visit a machine room during an open day event at a grain depot of Sinograin in Guangzhou, capital of south China's Guangdong Province, Oct. 14, 2019. The event was held to demonstrate modern, high-tech and intelligent grain depots of China's state grain stockpiler Sinograin. (Xinhua/Huang Guobao)