National Institute of Advanced Industrial Science and Technology (AIST) This page is a page of the former research institute. We stopped updating on March 31.2001.
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Time Standard

Second is the basic unit of time defined as the atomic energy of cesium.


Evolution of time and frequency standards.

Maintenance of Time and International Comparison

Electromagnetic waves are used in various ways in countries to compare time internationally and to maintain accuracy of time. Such data was used to construct the atomic clock. At NRLM, we have also contributed to the construction of the atomic clock by working out a time comparison to one millionth of a second using the Global Positioning System satellite.


International comparison of time.


Cesium frequency standards of NRLM.



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