The testings of 25 samples have shown that it is feasible to use ultrasonicspeed reduction index to evaluate the quality of concrete structures.
对25个样本的试验结果表明，以声波速度下降指数评定混凝土构件质量是可行的。
2
The field applications fo the last few years also indicate the method of ultrasonicspeed is a simple and easy way to assess the quality of concrete structures.
几年来的现场应用实跋，也说明声波速度法评定混凝土构件质量是一种简便易行的科学方法。
3
While the reentry target passes through the earths atmosphere at ultrasonicspeed, the RCS of the reentry Capsule changed violently because of the plasma sheath and wake.