BEIJING TIME-BPL AND BPM NATIONAL TIME SERVICE SYSTEMS

Time is a basic physical quantity.Time is an important technological support for scientific research and national construction. Many major countries in the world have their own independent standard time and perfect time service system.This book mainly introduces the composition and working principle of the BPL and BPM system, as well as the role of the BPL and BPM system in national construction and scientific research, and tries to answer some questions about time measurement, time characteristics and time application in popular language.