A visitor tries a vision tester during the 19th China-ASEAN Expo in Nanning, capital of south China's Guangxi Zhuang Autonomous Region, Sept. 17, 2022.Photo:Xinhua

A visitor tries a new energy car during the 19th China-ASEAN Expo in Nanning, capital of south China's Guangxi Zhuang Autonomous Region, Sept. 17, 2022.Photo:Xinhua

A visitor looks at a model of a self-driving bus during the 19th China-ASEAN Expo at Nanning International Convention and Exhibition Center in Nanning, capital of south China's Guangxi Zhuang Autonomous Region, Sept. 17, 2022.Photo:Xinhua

Photo taken on Sept. 17, 2022 shows an unmanned ship for ocean research during the 19th China-ASEAN Expo in Nanning, capital of south China's Guangxi Zhuang Autonomous Region.Photo:Xinhua

An exhibitor demonstrates a smart emergency communication system during the 19th China-ASEAN Expo in Nanning, capital of south China's Guangxi Zhuang Autonomous Region, Sept. 17, 2022.Photo:Xinhua