On June 20, 2021, China national clearing center (hereinafter referred to as "the clearing center ") was invited to participate in the celebration of the 20th anniversary of the founding of SEM and the "innovation and Development Forum", The signing ceremony of the agreement on joint training of postdoctoral researchers between SEM and the clearing center was held at the forum. Professor Yongmiao Hong, Dean of SEM, signed an agreement with Mr. Tielin He , Chief Engineer of the clearing center on behalf of each party.