随着现代科学技术的发展，频率及时间的测量以及它们的控制技术在科学技术各领域，特别是在计量学、电子技术、信息科学、通信、天文和电子仪器等领域占有越来越重要的地位。-With modern science and technology development, frequency and time measurement and control technology in their various fields of science and technology, especially in metrology, electronics technology, information science, communications, astronomy and electronic devices in areas such as possession of more and more important status.