Ying Li¹, Jianbo Li^1,*, Jianwei Chen¹, Minchao Lu¹, Caoyuan Li^2,3

CMC-Computers, Materials & Continua, Vol.57, No.3, pp. 571-587, 2018, DOI:10.32604/cmc.2018.02851

Abstract The explosive growth of mobile data demand is becoming an increasing burden on current cellular network. To address this issue, we propose a solution of opportunistic data offloading for alleviating overloaded cellular traffic. The principle behind it is to select a few important users as seeds for data sharing. The three critical steps are detailed as follows. We first explore individual interests of users by the construction of user profiles, on which an interest graph is built by Gaussian graphical modeling. We then apply the extreme value theory to threshold the encounter duration of user pairs. So, a contact graph… More >

Shuai Zhou^3,4, Xiaoying Zhuang^1,2,*

CMC-Computers, Materials & Continua, Vol.57, No.3, pp. 417-446, 2018, DOI:10.32604/cmc.2018.01742

Abstract The microcapsule-enabled cementitious material is an appealing building material and it has been attracting increasing research interest. By considering microcapsules as dissimilar inclusions in the material, this paper employs the discrete element method (DEM) to study the effects of loading rates on the fracturing behavior of cementitious specimens containing the inclusion and the crack. The numerical model was first developed and validated based on experimental results. It is then used to systematically study the initiation, the propagation and the coalescence of cracks in inclusion-enabled cementitious materials. The study reveals that the crack propagation speed, the first crack initiation stress, the… More >

Xiaodong Liu¹, Qi Liu^1,*

CMC-Computers, Materials & Continua, Vol.57, No.2, pp. 179-194, 2018, DOI:10.32604/cmc.2018.04025

Abstract In a home energy management system (HEMS), appliances are becoming diversified and intelligent, so that certain simple maintenance work can be completed by appliances themselves. During the measurement, collection and transmission of electricity load data in a HEMS sensor network, however, problems can be caused on the data due to faulty sensing processes and/or lost links, etc. In order to ensure the quality of retrieved load data, different solutions have been presented, but suffered from low recognition rates and high complexity. In this paper, a validation and repair method is presented to detect potential failures and errors in a domestic… More >

M. Ozisik^1,*, M. A. Mehdiyev², S. D. Akbarov^2,3

CMC-Computers, Materials & Continua, Vol.54, No.2, pp. 103-136, 2018, DOI:10.3970/cmc.2018.054.103

Abstract The dynamics of the moving-with-constant-velocity internal pressure acting on the inner surface of the hollow circular cylinder surrounded by an infinite elastic medium is studied within the scope of the piecewise homogeneous body model by employing the exact field equations of the linear theory of elastodynamics. It is assumed that the internal pressure is point-located with respect to the cylinder axis and is axisymmetric in the circumferential direction. Moreover, it is assumed that shear-spring type imperfect contact conditions on the interface between the cylinder and surrounding elastic medium are satisfied. The focus is on the influence of the mentioned imperfectness… More >

Yanbin Wang^1,2, Deli Gao¹, Jun Fang¹

CMC-Computers, Materials & Continua, Vol.48, No.1, pp. 25-42, 2015, DOI:10.3970/cmc.2015.048.025

Abstract In this paper, the buckling and collapse analysis of offshore pipeline under combined tension, bending moment, and external pressure has been presented with theoretical analysis and FE (finite element) simulation method respectively. Based on the model initially proposed by Kyriakides, a 2-D theoretical model has been further developed. To verify the correctness and accuracy of the model proposed in this paper, numerical simulations have been conducted with 3-D FE model using ABAQUS software. Good consistency has been shown between the calculation results which validate the availability of the theoretical analysis. On this basis, the influence of load path, material properties,… More >

W.Xu¹, A.M. Waas²

CMC-Computers, Materials & Continua, Vol.46, No.3, pp. 165-194, 2015, DOI:10.3970/cmc.2015.046.165

Abstract Plastic deformation and splitting are two important mechanisms of energy dissipation when metal tubes undergo axial crushing. Isotropic J2 plasticity theory combined with a failure criterion is used to model axial splitting and curling of metal tubes undergoing axial crush. The proposed material model is implemented within a finite element (FE) framework using the user material subroutine VUMAT option available in the commercial code ABAQUS. Experimental results from literature are used to validate the model. The predicted splitting and curling patterns as well as the load-displacement response agree well with the experimental observations. The present material model is also used… More >

D. Pandit¹, N. Thomas², Bhakti Patel¹, S.M. Srinivasan¹

CMC-Computers, Materials & Continua, Vol.45, No.2, pp. 127-144, 2015, DOI:10.3970/cmc.2015.045.127

Abstract In this paper, a class of problems involving space constrained loading on thin beams with large deflections is considered. The loading is such that, the locus of the force application point moves along an arbitrarily predefined path, fixed in space. Both linear elastic as well as elastic-perfectly plastic materials are considered. A simplification is realized using the moment-curvature relationship directly. The governing equation obtained is highly non-linear owing to inclusion of both material and geometric non-linearity. A general algorithm is described to solve the governing equation using an incremental formulation coupled with Runge Kutta 4^th order initial value explicit solver.… More >

S.D. Akbarov^1,2, M.I. Ismailov³

CMC-Computers, Materials & Continua, Vol.45, No.2, pp. 75-106, 2015, DOI:10.3970/cmc.2015.045.075

Abstract The subject of the paper is the study of the dynamics of the moving load acting on the hydro-elastic system consisting of the elastic plate, compressible viscous fluid and rigid wall. Under this study the motion of the plate is described by linear elastodynamics, and the motion of the compressible viscous fluid is described by the linearized Navier-Stokes equations. Numerical results are obtained for the case where the material of the plate is steel, but the fluid material is Glycerin. According to these results, corresponding conclusions related to the influence of the problem parameters, such as fluid viscosity, plate thickness,… More >

Qingsheng Yang^1,2, Shaochong Yang^1,3, Xiaohu Lin⁴

CMC-Computers, Materials & Continua, Vol.45, No.1, pp. 57-74, 2015, DOI:10.3970/cmc.2015.045.057

Abstract An equivalent continuum model of an isogrid structure is utilized to analyze the impact response of isogrid structures and stiffened structures. The parameters of the equivalent model are determined, and the comparison between the equivalent continuous structure and the real grid structure are examined to validate the reliability of the equivalent model. Then, the impact responses of stiffened cylindrical shells with and without an elliptical hole are investigated by using the equivalent model of grid structures. For a different location and geometry of the elliptical hole, the deformation and load-bearing capacity of the grid-stiffened cylindrical shells are studied. The numerical… More >

Wei Zhang^1,2, Pengcheng Ni², Bingfei Liu^1,3

CMC-Computers, Materials & Continua, Vol.44, No.2, pp. 105-122, 2014, DOI:10.3970/cmc.2014.044.105

Abstract Analytical expressions have been derived for the through thickness stresses of a Functional graded materials (FGMs) thin plate subjected to thermal loading, pure bending and thermo-mechanical coupling, respectively. The structure is comprised of a metallic layer, a ceramic layer and a functional graded layer. Continuous gradation of the volume fraction in the FGM layer is modeled in the form of an "m" power polynomial of the coordinate axis in thickness direction of the plate. Numerical scheme of discretizing the continuous FGM layer with different graded distributions such as linear (m=1), quadratic (m=2) and square root (m=0.5) has been developed by… More >