Dr. Ruoyu Liu pursued his doctor degree during 2012-2015 in the University of Heidelberg as a fellow of the International Max Planck Research School for Astronomy and Cosmic Physics. After that, he worked as a postdoctoral researcher at the Max-Planck-Institut für Kernphysik (MPIK) and Deutsches-Electronen Synchrotron (DESY) respectively, and went back to China as a researcher at Nanjing University in 2019. His research mainly focuses on, but not limited to,  high-energy and ultrahigh-energy cosmic rays, high-energy neutrinos, particle acceleration mechanism, and candidate sources of these particles such as pulsar wind nebula, gamma-ray burst, AGN jets and etc. He has published 80 papers in peer-reviewed international journal with a total citation over 3400 according to the NASA/ADS database.