Sign up for an Award
Participate with your entry in one of our professional or student awards.Sign up for an award
You are using an outdated browser. Please upgrade your browser to improve your experience.
When the well cover is lost,automatic alarm to remind people to have a hole, avoid pedestrians fall.Sound during the day time to remind people,and at night can emit light to remind people of.
Sang Yilei,Zhao Xiaoliang,Xue Mengru,Zhang Litao