Korean names are rendered in Chinese using the matching hanja (Sino-Korean characters) rather than phonetic guesswork:
金 (Kim, the most common Korean surname),
善 (sun/seon, 'good'),
明 (myeong, 'bright'). So
金善明 isn't a sound-by-sound transliteration but the original hanja form, read with Mandarin pronunciation. This is the standard convention for any Korean name in Chinese media.
