ALEXANDRIA, Va., March 17 -- United States Patent no. 12,578,499, issued on March 17.
"Land subsidence detection apparatus" was invented by Kwangik Kim (Seoul, South Korea).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention relates to a ground subsidence detection apparatus, which is capable of continuous detection of ground subsidence, predicts the occurrence of sinkholes and thus can preemptively prevent a sinkhole from forming, and due to having a simple structure, can increase durability and reduce cost. Provided is a ground subsidence detection apparatus exhibiting an alarm color using reflection of a light source and a detection weight, which, without using a separate power source, fal...