On June 27, 2024, as part of the APMP Mid-Year Meetings in Bohol, Philippines, a workshop on Establishing Traceability in Time and Frequency Measurements was conducted. The workshop's esteemed speaker was Dr. Jeffrey A. Sherman, Supervisory Physicist of the Time Realization and Distribution Group at the National Institute of Standards and Technology (NIST) – USA.

 Organized by the APMP and the host National Metrology Laboratory of the Philippines, this workshop was a timely and essential topic for developing economies seeking to establish traceability to the UTC. The workshop aimed to address the critical need for accurate and reliable time and frequency measurements, which serve as fundamental building blocks for various scientific, industrial, and technological applications.

 The workshop was formally opened by Dr. Annabelle V. Briones, Director of DOST-ITDI. In her remarks, Dr. Briones emphasized the importance of metrology in driving innovation and economic growth. She highlighted the role of accurate time and frequency measurements in ensuring the quality and reliability of products and services that rely on precise timekeeping.

 Dr. Hyun-Min Park, Chairperson of the APMP, delivered a message emphasizing the organization's commitment to fostering collaboration and knowledge sharing among its member economies. He noted that the workshop was a valuable opportunity for participants to learn from a world-renowned expert in the field of time and frequency metrology.

 Dr. Kazumoto Hosaka, Chair of the APMP-Technical Committee on Time and Frequency (TCTF), formally introduced Dr. Sherman and provided an overview of the workshop's objectives.

 The workshop was attended by participants from various APMP member economies, as well as Philippine local metrology laboratories, researchers, and academicians.

Dr. Sherman's comprehensive presentation covered five key areas:

-  Atomic Timekeeping: He delved into the physical basis of atomic timekeeping, basic spectral estimation, time-domain jargons, power law noise models, and Flicker and divergent noise types.

-  Time Domain Analysis: Dr. Sherman discussed the Allan Variance, its applications, and potential pitfalls, as well as high-resolution measurement techniques, modeling, and ensembling.

-  Building Blocks for a UTC(k) Time Scale Laboratory: He outlined the requirements, software, and hardware necessary for establishing a UTC(k) time scale laboratory.

-  GNSS Timing and Traceability: Dr. Sherman addressed the challenges and issues related to GNSS timing and traceability.

-  Network Time Transfer: He covered the basics of computer time, clocks, timescales, and geopolitics, as well as the Network Time Protocol, NIST's Internet Time Service, Precision Time Protocol, picoseconds on the network, and the new "Time over Fiber" NIST remote calibration service.

 Following his presentation, Dr. Sherman engaged in a lively Q&A session and interactive game with the workshop participants. The workshop was formally closed by Engr. Manuel M. Ruiz, Chief of NML-Philippines. Mr. Ruiz expressed his gratitude to Dr. Sherman for sharing his expertise and research, and highlighted the workshop's significance in advancing time and frequency metrology in the Philippines.

 The workshop was a resounding success, attracting a large number of interested local and international metrologists. Participants gained valuable knowledge and insights that they can apply in their work. The event showcased the importance of metrology in supporting economic development and technological progress both domestically and internationally.

 Looking forward, NMLPhil anticipates more such collaborative activities in the future to further advance the field of time and frequency metrology.

Contributor: Monalisa Enot, ITDI, Philippines