Old standards based on arbitrary authority or local traditions were replaced with mathematical and natural relationships.

基于任意权威或当地传统的旧标准被数学和自然关系所取代。

Interestingly, one of the standard base units is derived from an actual value though not a universal one.

有趣的是，其中一个标准基本单位源自实际值， 但不是通用值。

But thanks to improving technology and precision, these objects with limited access and unreliable longevity are now being replaced with standards based on universal constants, like the speed of light.

但由于技术和精度的提高，这些访问受限且寿命不可靠的物体现在正被基于通用常数（如光速）的标准所取代。