It does this by fitting small piezoelectric acoustic sensors to parts of the structure to detect the particular frequency of noise caused by a crack in aircraft-grade aluminium.
Engineering works mentioned herein refer to construction projects including the construction, reconstruction, extension, fitting, removal, repair of buildings and component parts.
本法所称工程，是指建设工程，包括建筑物和构筑物的新建、改建、扩建、装修、拆除、修缮等。
3
They produced each product piece by piece, making each part individually and fitting the parts into the finished product.