A.Lightactivation by stimulation emanation of radiation
B.Luminant amplimeter by stimulation emission of radiation
C.Lightactivation by strongemission of radiation
D.Luminant activation before strong emission of radiation
E.Light amplification by stimulation emisssion of radiation
A.單純隨機(jī)抽樣
B.系統(tǒng)抽樣
C.分層抽樣
D.整群抽樣
E.先分層抽樣再整群抽樣