The test results indicated that the strength of concrete could be estimated by supersonic velocity values.
结果表明由超声波测试得到的声速值可以方便地估算出混凝土的强度。
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Then, the base bleed method is introduced on a general supersonic missile to decrease the base drag of the inlet cowl for the first time and is validated by wind tunnel test.
This is Marine Corps Maj. Joseph Bachmann, a developmental test pilot for the Lockheed Martin-built supersonic strike fighter, in front of the F-35 AA-1 after a flight in March 2009.