An Automatic Hardness Measuring Method Using Hough Transform and Fuzzy C-means Algorithm. - Leehter Yao; Chih-Heng Fang (FUZZ-IEEE, 2001)

A hardness measuring method based on hough fuzzy vertex detection algorithm. - Leehter Yao; Chih-Heng Fang (IEEE Trans. Ind. Electron., 2006)