average velocity， mean velocity
group velocity and phase velocity
ratio of pulp velocity and sire velocity
velocity derived from velocity spectrum
approach of dilate-erode edge detection
Erode
伊洛德
冲刷
冲刷侵蚀
侵蚀
冲蚀
埃罗德
腐蚀
浸蚀
克洛德
膨胀
腐蚀成
腐蚀被腐蚀
逐渐消蚀掉
scaling-prevent and erode-slow agent