These so-called baryon acoustic oscillations offer another yardstick for measuring the expansion rate of the universe over time and putting limits on the value of dark energy.
这些被称为重子声学振荡的东西为测量随时间变化的宇宙的膨胀速度和对暗能量的值施加限制提供另一尺码。
2
The stress in ferromagnetic materials was studied by measuring the change of the amplitude of ultrasonic wave with electromagnetic acoustic transducers.
本文主要是对用电磁声换能器，通过测量超声波幅度变化来测量铁磁性材料内部应力的方法进行实验研究。
3
Echo Sounder is a kind of acousticmeasuring depth equipment, which can measure depth with the time between transmitted wave and echo on condition in which the speed of ultrasonic is fixed.