ty - jour a2 - 李，明·奥 - 廖，志武PY - 2013年DA - 2013/11/24 TI - 低温X射线计算机断层扫描成像通过正规化空间分数级梅罗纳 - 马利克扩散SP - 371868 VL -2013年 - 用于噪声抑制的现有分数级尿路 - Malik扩散（FOPMD）算法遭受不希望的伪影和散斑效果，其妨碍了用于低温X射线计算机断层扫描（LDCT）成像的FOPMD。In this paper, we propose a new FOPMD method for low-dose computed tomography (LDCT) imaging, which is called regularized fully spatial FOPMD (RFS-FOPMD), whose numerical scheme is also given based on Grünwald-Letnikov derivative (G-L derivative). Here, fully spatial FOPMD represents all the integer-order derivatives (IODs) in the right hand of Perona-Malik Diffusion (PMD) which are replaced by fractional-order derivatives (FODs). Since the new scheme has advantages of both regularization and FOPMD, it has good abilities in singularities preserving while suppressing noise. Some real sinogram of LDCT are used to compare the different performances not only for some classical but also for some state-of-art diffusion schemes. These schemes include PMD, regularized PMD (RPMD), and FOPMD in (Hu et al. 2012). Experimental results show that besides good ability in edge preserving, the new scheme also has good stability for iteration number and can avoid artifacts and speckle effect with suitable parameters. SN - 1687-9120 UR - https://doi.org/10.1155/2013/371868 DO - 10.1155/2013/371868 JF - Advances in Mathematical Physics PB - Hindawi Publishing Corporation KW - ER -