8Button J. Unified imaging approach for measuring aggregate angularity and texture [J]. Journal of Computer: Aided Civil and Infrastructure Engineering, 2000, 15(4) :273- 280.
9Masad E, Muhunthan B, Shashidhar N, Harman T.Internal structure characterization of asphalt concrete using image analysis [J ]. Journal of Computing in Civil Engineering (Special Issue on Image Processing)ASCE, 1999, 13(2): 88-95.
