Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded ta...Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded target is put forward and the non-coded and coded targets are classified. Moreover, the gray scale centroid algorithm is applied to obtain the subpixel location of both uncoded and coded targets. The initial matching of the uncoded target correspondences between an image pair is established according to similarity and compatibility, which are based on the ID correspondences of the coded targets. The outliers in the initial matching of the uncoded target are eliminated according to three rules to finally obtain the uncoded target correspondences. Practical examples show that the algorithm is rapid, robust and is of high precision and matching ratio.展开更多
The characteristics of asphalt mixtures are associated with the key features of the mixed material when it is not damaged.Two-dimensional(2D) microstructure images of asphalt mixture bending beam specimen were capture...The characteristics of asphalt mixtures are associated with the key features of the mixed material when it is not damaged.Two-dimensional(2D) microstructure images of asphalt mixture bending beam specimen were captured by a CCD camera.After image processing,such as noise elimination,boundary identification,image binarization and vectorization,the images were imported into finite element(FE) software in order to set up the micromechanical finite element(FE) model.The simulation results show that the displacement contours spectrum is not a smooth curve since the mixed material is heterogeneous.Also,the largest strain value exists at the bottom of the specimen between two coarse aggregates,and it is the point where the fracture starts.The stress values of aggregates are larger than those of the asphalt matrix.Different from the strain of asphalt matrix,the strain of aggregates is close to zero because the aggregates have higher capability to resist self-deformation.The difference in deformation between aggregate and asphalt matrix can lead to an interface crack as a final result.All these results can be improved by three-point bending test of asphalt mixture beam.展开更多
基金The National Natural Science Foundation of China(No50475041)
文摘Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded target is put forward and the non-coded and coded targets are classified. Moreover, the gray scale centroid algorithm is applied to obtain the subpixel location of both uncoded and coded targets. The initial matching of the uncoded target correspondences between an image pair is established according to similarity and compatibility, which are based on the ID correspondences of the coded targets. The outliers in the initial matching of the uncoded target are eliminated according to three rules to finally obtain the uncoded target correspondences. Practical examples show that the algorithm is rapid, robust and is of high precision and matching ratio.
基金supported by the National Natural Science Foundation of China (Grant No. 11162010)the Inner Mongolia Natural Science Foundation (Grant No. 2009MS0701)
文摘The characteristics of asphalt mixtures are associated with the key features of the mixed material when it is not damaged.Two-dimensional(2D) microstructure images of asphalt mixture bending beam specimen were captured by a CCD camera.After image processing,such as noise elimination,boundary identification,image binarization and vectorization,the images were imported into finite element(FE) software in order to set up the micromechanical finite element(FE) model.The simulation results show that the displacement contours spectrum is not a smooth curve since the mixed material is heterogeneous.Also,the largest strain value exists at the bottom of the specimen between two coarse aggregates,and it is the point where the fracture starts.The stress values of aggregates are larger than those of the asphalt matrix.Different from the strain of asphalt matrix,the strain of aggregates is close to zero because the aggregates have higher capability to resist self-deformation.The difference in deformation between aggregate and asphalt matrix can lead to an interface crack as a final result.All these results can be improved by three-point bending test of asphalt mixture beam.