Introduction to Activities of AI and Digital Twin WG in XGMF 6G Radio Technology Project. - Tetsuya Yamamoto; Takahiro Yamazaki; Tomoaki Otsuki; Satoshi Suyama; Liqing Liu; Noboru Osawa; Hiroto Yamamoto; Taishi Watanabe; Keita Kuriyama; Takashi Koshimizu; Yu Tsukamoto; Hiromichi Tomeba; et al. (APWCS, 2025)