Ultrasound is a safe, non-invasive, FDA approved diagnostic test that USES sound waves to measure blood-flow velocity in large arteries.

超声波是FDA认可的一种安全的非侵入性诊断实验项目，利用声波来测量大动脉血管中的血液流速。

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The shocking safety distances for blasting with various charges and safe charge for specific distance are both determined according to the particle vibration velocity safety control standard.

根据质点振速的安全控制标准，确定了不同药量爆破的震动安全距离，以及确定距离的安全药量。

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It has advantages such as large transport capacity, high velocity, safe, punctuality, low cost, energy conservation, as well as mitigation of ground traffic jam and environment protection.

它具有运能大、速度快、安全准时、成本低、节约能源、以及能缓解地面交通拥挤和有利于环境保护等优点。

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