gray scale
灰度
灰阶
灰
灰度等级
灰度级
灰色刻度
摄灰色级谱
灰度标
灰度值
灰阶标度
灰度尺
硅片的格雷
色量级
灰黑比
多灰阶
灰梯尺
Gray scale display and color doppler flow imaging
gray scale equilibrium technology
gray scale pattern recognition
correction of scale difference
difference in difference
difference in difference (DD) method
Difference-in-difference
Acipenser sinensis Gray