Национальный институт интеллектуальной собственности
At 57 years old, Li Keren is at an age when most people start thinking about retirement.
But instead Mr Li has turned his hobby into a business and became an entrepreneur designing model aircraft.
But what makes Mr Li proudest are his innovations in the plane's design. He has built remote-controlled doors on the bottom of the aircraft that mean you can drop firecrackers when it is in flight.
It is all a bit of fun, he insists. But Mr Li is serious about protecting his designs.
"I fear that if I don't have a patent for my design that it would simply get stolen. For that reason, I don't even give people a drawing of my plan when asked."
