VOA News 조회 수 229 추천 수 0 2015.03.19 03:55:49
Finding hidden cracks in large structures, such as bridges and airplanes, can be the difference between life and death, if the flaw leads to a catastrophic collapse. Scientists at Bristol...
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원문출처 : http://www.youtube.com/watch?v=zHPMBZSOHks&feature=youtube_gdata