Zhe Liu^1,2,*, Bao Xiang^1,3, Yuqing Song¹, Hu Lu¹, Qingfeng Liu¹

CMC-Computers, Materials & Continua, Vol.58, No.2, pp. 451-461, 2019, DOI:10.32604/cmc.2019.04069

Abstract Most image segmentation methods based on clustering algorithms use single-objective function to implement image segmentation. To avoid the defect, this paper proposes a new image segmentation method based on a multi-objective particle swarm optimization (PSO) clustering algorithm. This unsupervised algorithm not only offers a new similarity computing approach based on electromagnetic forces, but also obtains the proper number of clusters which is determined by scale-space theory. It is experimentally demonstrated that the applicability and effectiveness of the proposed multi-objective PSO clustering algorithm. More >

F. Wang^1,2, D.M. Zhang^1,2,3, H.H. Zhu⁴, H.W. Huang^1,2, J.H. Yin⁵

CMC-Computers, Materials & Continua, Vol.34, No.1, pp. 63-81, 2013, DOI:10.3970/cmc.2013.034.063

Abstract This paper studies the impact of overhead excavation on an existing tunnel through both field monitoring and a full 3D numerical model. It is found that the excavation induced longitudinal heave of the tunnel is uneven with maximum heave occurring below the excavation center. Even at the same cross section, the excavation induced heave is not uniform with the most significant heave occurring at the tunnel crown. The bending moments of the tunnel lining is decreased due to the overhead excavation. The axial forces of the tunnel lining generally decrease except at the tunnel invert. The shear forces of the… More >

Hao-Miao Zhou^1,2, You-He Zhou¹, Xiao-Jing Zheng¹, Jing Wei³

CMC-Computers, Materials & Continua, Vol.12, No.3, pp. 237-250, 2009, DOI:10.3970/cmc.2009.012.237

Abstract From the viewpoint of energy, a general magnetoelastic coupling theory including magnetic forces and magnetostriction effects is proposed for deformable magnetized medium. Firstly, a Taylor series expansion of independent variables of stress and magnetization in the elastic Gibbs free energy function is applied to obtain a polynomial expression; and then based on the magnetoelastic coupling mechanism, appropriate transcendental functions are substituted for some terms in a polynomial constitutive relationship derived by way of substituting the polynomial Gibbs free energy function in thermodynamic equations to achieve a more compact magnetostrictive constitutive relationship. The numerical simulation exhibits that the predicted magnetostrictive strain… More >

R. Gangadharan¹, A. Rajagopal¹, S.M. Sivakumar^{1, 2}

CMC-Computers, Materials & Continua, Vol.1, No.3, pp. 229-244, 2004, DOI:10.3970/cmc.2004.001.229

Abstract A new r-h adaptive scheme is proposed and formulated. It involves a combination of the configurational force based r-adaption with weighted Laplacian smoothing and mesh enrichment by h-refinement. A Zienkiewicz-Zhu best guess stress error estimator is used in the h-refinement strategy. The best sequence for combining the effectiveness of r- and h- adaption has been evolved at in this study. A further reduction in the potential energy and the relative error norm of the system is found to be achieved with combined r-adaption and mesh enrichment (in the form h-refinement). Numerical study confirms that the proposed combined r-h adaption is… More >