[经] operation research and synthesis
jīng yíng yè wù de zōng hé yán jiū ㄐㄧㄥ ㄧㄥˊ ㄧㄝˋ ㄨˋ ㄉㄜ˙ ㄗㄨㄥ ㄏㄜˊ ㄧㄢˊ ㄐㄧㄡ