ALEXANDRIA, Va., June 16 -- United States Patent no. 12,305,654, issued on May 20, was assigned to Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (Gansu, China).

"Fully automatic device for pumping cold air into block-stone subgrade" was invented by Yasheng Li (Gansu, China), Zhi Wen (Gansu, China), Fei Wang (Gansu, China) and Kun Xiang (Gansu, China).

According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention discloses a fully automatic device for pumping cold air into block-stone subgrade and includes an outer cylinder, an inner cylinder, a power system and an air pumping system; and utilizes natural wind to drive the air pumping system to operate for the purpose ...