in src/main/scala/com/twitter/penguin/korean/util/KoreanSubstantive.scala [36:39]
protected[korean] def isJosaAttachable(prevChar: Char, headChar: Char): Boolean = {
(hasCoda(prevChar) && !JOSA_HEAD_FOR_NO_CODA.contains(headChar)) ||
(!hasCoda(prevChar) && !JOSA_HEAD_FOR_CODA.contains(headChar))
}