1949: Starting from Northeast China

Jiang Fan, a hardcore science blogger, received a mysterious watch but was pulled into a white space with a 72-hour countdown. When he opened his eyes again, he found himself in Anshan Iron and Steel Company in 1949, a time of rebuilding after the war. Intending to spend three days there and then go home, his Western-style attire and his ability to speak English and read blueprints led him directly to a small white building. The meeting room was filled with smoke, and the eyes of a dozen leaders were fixed on him. "Young man, studying mechanical engineering? Perfect, we have a difficult problem that has been bothering us for days." What?! He's supposed to solve a technical problem for Anshan Iron and Steel Company in 1949?!