短语词组短語tactor r 觸器damping tactor 阻尼因素environment tactor 環境因子compensating tactor 補償系數etiological tactor 病因tactor or actress 觸器con -tactor competition 觸點競爭power utilization tactor 電源利用系數dose modifying tactor 劑量脩正因素 返回 tactor