M. Morii¹, N. Hu^1,2, H. Fukunaga³, J.H. Li¹, Y.L. Liu¹, S. Atobe³, Alamusi³, J.H. Qiu⁴

CMC-Computers, Materials & Continua, Vol.26, No.1, pp. 37-66, 2011, DOI:10.3970/cmc.2011.026.037

Abstract Lamb wave tomography (LWT) is a potential and efficient technique for non-destructive tomographic reconstruction of damage images in structural components or materials. A new two-stage inverse algorithm with a small amount of scanning data for quickly reconstructing damage images in aluminum and CFRP laminated plates was proposed in this paper. Due to its high sensitivity to damages, the amplitude decrease of transmitted Lamb waves after travelling through the inspected region was employed as a key signal parameter related to the attenuation of Lamb waves in propagation routes. A through-thickness circular hole and a through-thickness elliptical hole in two aluminum plates,… More >

Yong Jiang¹, Xiaolin Zhong^1,*, Yong Guo¹, Meixia Duan²

CMC-Computers, Materials & Continua, Vol.57, No.2, pp. 321-340, 2018, DOI:10.32604/cmc.2018.03796

Abstract The emergency communication system based on rail is an unconventional emergency communication mode, it is a complement equipment for that conventional communication system can’t work while tunnel mine accident occurs. Medium of transmission channel is the widely existing rail in the tunnel. In this paper we analyzed the characteristics of the rail transmission channel, verified the feasibility that information is transmitted by vibration signal in rail, we proposed the realization plan of the system. Communication protocol and processing mechanism suitable for rail transmission are designed according to the characteristics of channel bandwidth and low data transmission. Information communication with low… More >

S.D. Akbarov^1,2, T. Kocal³, T. Kepceler¹

CMC-Computers, Materials & Continua, Vol.51, No.2, pp. 105-143, 2016, DOI:10.3970/cmc.2016.051.105

Abstract The paper studies the dispersion of axisymmetric longitudinal waves in the bi-material compound circular cylinder made of linear viscoelastic materials. The investigations are carried out within the scope of the piecewise homogeneous body model by utilizing the exact equations of linear viscoelasto-dynamics. The corresponding dispersion equation is derived for an arbitrary type of hereditary operator and the algorithm is developed for its numerical solution. Concrete numerical results are obtained for the case where the relations of the constituents of the cylinder are described through fractional exponential operators. The influence of the viscosity of the materials of the compound cylinder on… More >

P.G. Santos¹, J. Carbajo², L. Godinho³, J. Ramis²

CMC-Computers, Materials & Continua, Vol.43, No.2, pp. 109-136, 2014, DOI:10.3970/cmc.2014.043.109

Abstract The study of periodic structures, namely sonic crystals, for sound attenuation purposes has been a topic of intense research in the last years. Some efficient methods are available in literature to solve the problem of sound propagation in the presence of this kind of structures such as those based in the Multiple Scattering Theory (MST) or the Finite Element Method (FEM). In this paper a solution based on the Method of Fundamental Solutions (MFS) which presents advantages, namely in computational discretization and calculation costs, is presented. The proposed formulation considers the presence of elastic ring shaped scatterers, correctly accounting for… More >