我们往往低估了使用超声波的动物的能力有多复杂。
We have tended to underestimate just how sophisticated the abilities of animals that use ultrasound are.
与光子或声波的物理实体不同，感知是大脑的产物。
More than the physical reality of photons or sound waves, perception is a product of the brain.
那是音叉发出的声波的干涉的结果。
声波的传播需要媒介，这种媒介可以是空气、水、玻璃或金属。
Sound waves need a medium through which to travel, whether it's air, water, glass or metal.
主要波跟声波的特征相同，当地面被加压或减压时强迫向前和向后移动。
Primary waves are identical in character to sound waves. The ground is forced to move forwards and backwards as it is compressed and decompressed.
例如，当神经细胞与超声波的距离过短时，细胞会因加热而致死。
When nerve cells were exposed to it at close range, for example, they heated up and died.
如果传播路径上有一个黑子区，（声波的）传播时间将会短一些。
If there is a sunspot region along one of these paths, the travel time will be a little bit shorter.
当纤维在声波的作用下发出振动时，它会产生一种能够被探测到的电子信号。
When acoustic waves cause the fibre to vibrate, it produces a corresponding electrical signal that can be detected.
这就是为什么我们能在一个充满各个方向回声声波的房间中辨认声音位置的原因。
This is why we are still able to localize sounds in an echoey room where reflecting sound waves come from different directions.
在地表，这种类似于低频声波的振动非常小，只相当于造成它们的垂直振动的幅度。
At ground level, such vibrations-akin to low-frequency sound waves-are very small, only about the size of the vertical motions that produce them.
换言之，基本上超声波的传播声束极窄，这非常有利于将声波集中至指定地点，但对实际听力则无所助益。
In other words, ultrasound essentially travels in a very narrow beam — this makes it great for focusing the waves toward a desired area, but not for actual aural comprehension.
每隔几天，就有人从“大耳朵”（俄亥俄州立大学的巨型射线望远镜）骑自行车过来，并交给他由外太空传来的声波的电脑记录。
Every few days, a messenger would bike over from "The Big Ear, " Ohio State's giant radio telescope in Delaware, Ohio, and hand Jerry computer records of sounds coming in from deep space.
“我们能探测六万公里深处的黑子，但如果探测更深些或者更靠近太阳表面的位置时，(声波的)传播时间的变化将变得不明显，”Ilonidis说。
"We can detect sunspots at a depth of 60,000 kilometers, but if we try to detect them deeper or closer to the surface, the travel-time shift becomes weaker," Ilonidis says.
“我们能探测六万公里深处的黑子，但如果探测更深些或者更靠近太阳表面的位置时，(声波的)传播时间的变化将变得不明显，”Ilonidis说。
"We can detect sunspots at a depth of 60, 000 kilometers, but if we try to detect them deeper or closer to the surface, the travel-time shift becomes weaker," Ilonidis says.
这个场景非常新奇刺激，但有个小问题，声波是不能在真空中传播的。
It makes for a very cool and exciting scene, except for one small problem: Sound waves can't travel in a vacuum.
他们希望将这种材料进一步完善，届时类似声波之类的小干扰将能用于收集能源。
They had hoped to be able to perfect this material so that small disturbances, including sound waves, could be harvested for energy.
蝙蝠用超声波识别猎物发出的震动。
利用声波来为类似手机的小型设备充电，早已不是一个新想法了。
Using sound waves to charge small devices like cell phones is not a brand new idea.
这些大气波动携带的能量像声波那样在水平方向和垂直方向上进行传播。
The energy from these atmospheric waves, like the energy from a sound wave, propagates both horizontally and vertically.
换能器由阵列微压电结构组成，这种压电材料在合适频率下的振动能够将电信号转换成超声波。
Transducers are made from arrays of tiny piezoelectric structures that convert electrical signals into ultrasound waves by vibrating at an appropriate frequency.
所以蝙蝠发出这些脉冲，一种非常集中的声波，然后回声就会反弹回来。
So the bat sends out these pulses, very focused bursts of sound, and echoes bounce back.
第一个是晶体乳化技术，它使用一根细小的超声波探针去移除晶体。
The first, phakoemulsification, uses a tiny ultrasound probe to remove the lens.
不过，对测定目标物距离来说，声波运行的速度太慢，因此，声波回声测距法在实用中有其局限性。
Thus this soundwave echo method has its limitation in practical use.
随后它便产生逆向声波从而消除耳机信号中不需要的噪声。
It produces an inverted sound wave to cancel out unwanted noise in the headphone signal.
然而，韩国科学家想驾驭一种不同类型的能量源，那就是声波。
The Korean scientists, however, want to harness a different kind of power source: sound waves.
系统发射出的声波窄射线在300米(约1000英尺)开外也能清晰听到。
It fires narrow beams of sound waves that can be heard clearly from 300 meters (about a thousand feet) away.
声波能产生大约50毫伏的微弱电流。
The sound waves produced a mild electrical current of about 50 millivolts.
德国的电子和工程巨头西门子，最近发布了一套超声波扫描仪，可以让孕妇看到待产胎儿的3维影像。
And Siemens, a German electronics and engineering giant, recently launched an ultrasound scanner which allows expectant mothers to see their unborn child in 3-d.
德国的电子和工程巨头西门子，最近发布了一套超声波扫描仪，可以让孕妇看到待产胎儿的3维影像。
And Siemens, a German electronics and engineering giant, recently launched an ultrasound scanner which allows expectant mothers to see their unborn child in 3-d.
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