DAVOS, Jan. 20, 2016 (Xinhua) -- German President Joachim Gauck delivers a speech at an annual meeting of the World Economic Forum (WEF) in Davos, Switzerland, Jan. 20, 2016. The leaders from various key sectors highlighted the 4th industrial revolution will be driven by renewable energy at the 46th WEF annual meeting, which kicked off on Wednesday in Davos-Klosters, Switzerland. (Xinhua/WORLD ECONOMIC FORUM/Remy Steinegger)