noise reduction 噪声
低，噪声消减 cost reduction 成本低 reduction method 还原法；设置限制方法
reduction process 还原过程；减除作业
direct reduction 直接还原；直接归约
drag reduction 减阻
reduction ratio 减速比
reduction rate 还原速度；减速率
weight reduction 减重
open reduction 切开复位术
dimensionality reduction 维 reduction reaction 还原反应
data reduction 数据简化；资料缩减
chemical reduction 化学还原
tax reduction 减税
reduction gear 减速齿轮；减速装置
temperature reduction 温度下 pressure reduction 减压
reduction cell 电解槽；电解还原槽；还原槽
，
加，
；减
