Peter L. Bishay¹, Jan Sladek², Vladimir Sladek², Satya N. Atluri¹

CMC-Computers, Materials & Continua, Vol.29, No.3, pp. 213-262, 2012, DOI:10.3970/cmc.2012.029.213

Abstract A new class of hybrid/mixed finite elements, denoted "HMFEM-C", has been developed for modeling magneto-electro-elastic (MEE) materials. These elements are based on assuming independent strain-fields, electric and magnetic fields, and collocating them with the strain-fields, electric and magnetic fields derived from the primal variables (mechanical displacements, electric and magnetic potentials) at some cleverly chosen points inside each element. The newly developed elements show significantly higher accuracy than the primal elements for the electric, magnetic as well as the mechanical variables. HMFEM-C is invariant through the use of the element-fixed local orthogonal base vectors, and is stable since it is not… More >

L. Dong¹, S. N. Atluri¹

CMC-Computers, Materials & Continua, Vol.29, No.2, pp. 169-212, 2012, DOI:10.3970/cmc.2012.029.169

Abstract In this paper, three-dimensionalT-Trefftz Voronoi Cell Finite Elements (VCFEM-TTs) are developed for micromechanical modeling of heterogeneous materials. Several types of VCFEMs are developed, depending on the types of heterogeneity in each element. Each VCFEM can include alternatively a spherical void, a spherical elastic inclusion, a spherical rigid inclusion, or no voids/inclusions at all.In all of these cases, an inter-element compatible displacement field is assumed at each surface of the polyhedral element, with Barycentric coordinates as nodal shape functions.The T-Trefftz trial displacement fields in each element are expressed in terms of the Papkovich-Neuber solution. Spherical harmonics are used as the Papkovich-Neuber… More >

J. Sladek¹, V. Sladek¹, S. Krahulec¹, M. Wünsche², Ch. Zhang²

CMC-Computers, Materials & Continua, Vol.29, No.1, pp. 75-102, 2012, DOI:10.3970/cmc.2012.029.075

Abstract A meshless method based on the local Petrov-Galerkin approach is proposed, to solve static and dynamic problems of two-layered magnetoelectroelastic composites with specific properties. One layer has pure piezoelectric properties and the second one is a pure piezomagnetic material. It is shown that the electric potential in the piezoelectric layer is induced by the magnetic potential in the piezomagnetic layer. The magnetoelectric effect is dependent on the ratio of the layer thicknesses. Functionally graded material properties of the piezoelectric layer and homogeneous properties of the piezomagnetic layer are considered too. The magnetoelectric composites are analyzed under a pure magnetic or… More >

J. Zidek^1,2, J. Kucera¹, J. Jancar^1,2

CMC-Computers, Materials & Continua, Vol.28, No.3, pp. 213-230, 2012, DOI:10.3970/cmc.2012.028.213

Abstract The paper presents a combination of worm-like chain numerical models and one with a finite set of nano-particles. The primary objective of the models was to analyze the distribution of space in a system filled by particles. Information on the distribution of space was compared to properties of chains inside the set of particles. The set of nanoparticles was constructed with a tool generating a finite set of particles that is randomly distributed in a given space. The particles have a prescribed volume fraction and uniform size. First, the proportions of chains and particles were compared. The length of chain… More >

E. Ferretti¹, M.C. Bignozzi²

CMC-Computers, Materials & Continua, Vol.27, No.3, pp. 231-274, 2012, DOI:10.3970/cmc.2011.027.231

Abstract In this study, the results of an in-situ experimental program on the performance of concrete taxiways are presented. The experimental program has been undertaken at the Guglielmo Marconi airport of Bologna (Italy). It concerns two portions of the taxiway, one built with plain concrete and one with rubberized concrete. Each portion has been instrumented with strain gauges embedded in concrete for the acquisition of vertical strains. The results of the experimentation are discussed in view of possible applications to the computational analysis of the stress field induced into pavements by aircrafts. More >

Ying Xiao¹, Hao-Miao Zhou^1,2,3, Xiao-Wei Ou¹, Chao Li¹

CMC-Computers, Materials & Continua, Vol.27, No.1, pp. 1-22, 2012, DOI:10.3970/cmc.2012.027.001

Abstract Considering the complex strongly nonlinear coupling characteristic of the magnetostrictive strain and magnetization under the excitation of the bias magnetic field and the pre-stress in the giant magnetostrictive material, this paper adopts the nonlinear magnetostrictive constitutive model and the equivalent circuit method to establish a strongly nonlinear resonant magnetoelectric (ME) effect theoretical model for the ME laminate composites compounding by the giant magnetostrictive material and the piezoelectric material. For the L-T mode magnetostrictive/piezoelectric/magnetostrictive (MPM) ME laminate, the predicted results coincide well with the experiment results of the resonant frequency and the resonant ME field coefficient varying with the external magnetic… More >

De-Shin Liu¹, Zhen-Wei Zhuang¹, Shaw-Ruey Lyu^2,3, Cho-Liang Chung⁴, Pai-Chen Lin¹

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 111-136, 2011, DOI:10.3970/cmc.2011.026.111

Abstract This study proposes a two-dimensional heterogeneous hybrid moisture element method (HHMEM) for modeling transient moisture diffusion in permeable fiber-reinforced polymer composites.
The HHMEM scheme is based on a heterogeneous hybrid moisture element(HHME), with properties determined through an equivalent hybrid moisture capacitance/conductance matrix. This matrix was calculated using the conventional finite element formulation in space discretization as well as the θ-method in time discretization with similar mass/stiffness properties and matrix condensing operations. A coupled HHME-FE scheme was developed and implemented in computer code MATLAB in order to analyze the transient moisture diffusion characteristics of composite materials containing multiple permeable fibers. The… More >

V.K. Tewary¹, M. D. Vaudin²

CMC-Computers, Materials & Continua, Vol.25, No.3, pp. 265-290, 2011, DOI:10.3970/cmc.2011.025.265

Abstract A semicontiuum Green's-function-based model is proposed for analysis of averaged mechanical characteristics of Si_xGe_{1 - x}. The atomistic forces in the model are distributed at discrete lattice sites, but the Green's function is approximated by the continuum GF in the far field and by the averaged lattice GF in the near field. Averaging is achieved by replacing Si and Ge atoms by identical hypothetical atoms that are x fraction Si and (1-x) fraction Ge. The parameters of the model are derived using the atomistic model from the interatomic potential between the hypothetical atoms. The interatomic potential is obtained from the… More >

Zhiguo Qu^1,*, Tiancheng Zhu², Jinwei Wang¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.56, No.1, pp. 47-59, 2018, DOI: 10.3970/cmc.2018.02215

Abstract In this paper, a novel quantum steganography protocol based on Brown entangled states is proposed. The new protocol adopts the CNOT operation to achieve the transmission of secret information by the best use of the characteristics of entangled states. Comparing with the previous quantum steganography algorithms, the new protocol focuses on its anti-noise capability for the phase-flip noise, which proved its good security resisting on quantum noise. Furthermore, the covert communication of secret information in the quantum secure direct communication channel would not affect the normal information transmission process due to the new protocol’s good imperceptibility. If the number of… More >

Zihao Yang¹, Junzhi Cui², Yufeng Nie¹, Yatao Wu¹, Bin Yang³, Bo Wu⁴

CMC-Computers, Materials & Continua, Vol.38, No.3, pp. 175-194, 2013, DOI:10.3970/cmc.2013.038.175

Abstract This study is concerned with the microstructural modeling and mechanical properties computation of three-dimensional (3D) 4-directional braided composites. Microstructure of the braided composite determines its mechanical properties and a precise geometry modeling of the composite is essential to predict the material properties. On the basis of microscopic observation, a new parameterized microstructural unit cell model is established in this paper. And this model truly simulates the microstructure of the braided composites. Furthermore, the mathematical relationships among the structural parameters, including the braiding angle, fiber volume fraction and braiding bitch, are derived. By using the unit cell model, the second-order two-scale… More >