Học tiếng Anh: http://www.facebook.com/Words.and.Idioms hiệu quả, nhanh chóng: Các chương trình của VOA Learning English for Vietnamese (http://www.voatiengviet.com/section/hoc-tieng-anh/2693.html) có thể giúp các bạn cải tiến kỹ năng nghe, hiểu rõ cấu trúc và ngữ pháp, và sử dụng Anh ngữ một cách chính xác.
Luyện nghe nói tiếng Anh qua video: Chương trình học tiếng Anh của VOA: Special English Technology Report. Xin hãy vào http://www.voatiengviet.com/section/hoc-tieng-anh/2693.html để xem các bài kế tiếp.
When a building collapses, every minute is important for people buried under the wreckage. That is why two American government agencies worked together to develop a high-technology tool to find those trapped. The Department of Homeland Security and NASA, the American space agency, took part in the project. Rescue crews have been testing this radar tool called FINDER. The name is short for Finding Individuals for Disaster and Emergency Response. The device can recognize the smallest movements or even a heartbeat, even when a person is unable to speak. Earlier this year, rescue crews used FINDER to carry out more than 65 test searches in the American state of Virginia. Crew members say the device recognized a human heartbeat under nine meters of mixed concrete and other material. It also was able to identify a heartbeat hidden behind six meters of solid concrete, and from a distance of up to 30 meters in open space. FINDER is an example of how space agency creations are helping people here on Earth. FINDER works by sending a low-power microwave signal into a collapsed structure. Some of the microwaves reflect off the victim and come back out. So FINDER sees both the reflection from the wreckage and a very small reflection from the victim. It can also recognize the victim’s breathing and heartbeat. The radar tool is small, easy to carry and easy to use. FINDER could be used with other rescue tools such as listening devices or search dogs. The device is still being tested. But NASA officials say it could ready for use in search and rescue operations as early as next year.
