G. Q. Xie^1,2,3, X. Han², S. Y. Long³

CMC-Computers, Materials & Continua, Vol.6, No.1, pp. 1-12, 2007, DOI:10.3970/cmc.2007.006.001

Abstract A multi-walled carbon nanotube is modeled as a multiple-elastic cylindrical structure. The numerical-analytical method is adopted to analyze the characteristics of harmonic waves propagating along an anisotropic carbon nanotube. Each wall of the carbon nanotube is divided into three-nodal-line layer elements. The deflections of two adjacent tubes are coupled through the van der Waals. The governing equation of element is obtained from Hamilton's principle. A set of system equation of dynamics equilibrium for the entire structure is obtained by the assembling of all the elements. From solution of the eigenvalue equations, the dispersive characteristics, group velocities of multi-walled carbon nanotubes… More >

G. Q. Xie^1,2, S. Y. Long^1,3

CMC-Computers, Materials & Continua, Vol.4, No.1, pp. 11-20, 2006, DOI:10.3970/cmc.2006.004.011

Abstract The concept of the micropolar theory is employed to investigate vibration behaviors of carbon nanotubes. The constitutive relation has been deduced from the two-dimensional analysis of the microstructure of the carbon nanotube. Van der Waals interactions are simulated by a weak spring model. Hamilton's principle is employed to obtain dynamics equations of the multi-walled carbon nanotube. Numerical examples for both single-walled and double-walled carbon nanotubes are presented and the significant difference in vibration behaviors between them has been distinguished. Numerical results show that fundamental frequencies for the cantilever single-walled carbon nanotube decreases with increase of the aspect ratio of them,… More >

Yong Fang¹, Yunyun Zhang², Cheng Huang^1,*

CMC-Computers, Materials & Continua, Vol.61, No.1, pp. 185-195, 2019, DOI:10.32604/cmc.2019.06144

Abstract In recent years, the rapid development of e-commerce exposes great vulnerabilities in online transactions for fraudsters to exploit. Credit card transactions take a salient role in nowadays’ online transactions for its obvious advantages including discounts and earning credit card points. So credit card fraudulence has become a target of concern. In order to deal with the situation, credit card fraud detection based on machine learning is been studied recently. Yet, it is difficult to detect fraudulent transactions due to data imbalance (normal and fraudulent transactions), for which Smote algorithm is proposed in order to resolve data imbalance. The assessment of… More >

Liang Kou¹, Yiqi Shi², Liguo Zhang¹, Duo Liu^1,*, Qing Yang³

CMC-Computers, Materials & Continua, Vol.58, No.2, pp. 545-565, 2019, DOI:10.32604/cmc.2019.03760

Abstract With the development of computer hardware technology and network technology, the Internet of Things as the extension and expansion of traditional computing network has played an increasingly important role in all professions and trades and has had a tremendous impact on people lifestyle. The information perception of the Internet of Things plays a key role as a link between the computer world and the real world. However, there are potential security threats in the Perceptual Layer Network applied for information perception because Perceptual Layer Network consists of a large number of sensor nodes with weak computing power, limited power supply,… More >

Puneet Kumar^1,*, J. Srinivas²

CMC-Computers, Materials & Continua, Vol.54, No.1, pp. 1-20, 2018, DOI:10.3970/cmc.2018.054.001

Abstract Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube (CNT) reinforced polymer composites recently. This paper presents the composite cylinder assemblage (CCA) approach based on continuum mechanics for investigating the elastic properties of a polymer resin reinforced by multi-walled carbon nanotubes (MWCNTs). A three-phase cylindrical representative volume element (RVE) model is employed based on CCA technique to elucidate the effects of inter layers, chirality, interspacing, volume fraction of MWCNT, interphase properties and temperature conditions on the elastic modulus of the composite. The interface region between CNT and polymer matrix is modeled… More >

Wenxiang Xu^1,2,3,4, Ganquan Yang⁵, Peng Lan², Huaifa Ma¹

CMC-Computers, Materials & Continua, Vol.52, No.1, pp. 25-40, 2016, DOI:10.3970/cmc.2016.052.025

Abstract Understanding the excluded volume of anisotropic particle is of great importance in the evaluation of continuum percolation and random packing behaviors of soft/hard particle systems in heterogeneous disordered media. In this work, we obtain the excluded volumes of several anisotropic convex particles including prolate spheroids, oblate spheroids, spherocylinders, and Platonic particles, using theoretical and numerical approaches. According to the second virial coefficient, we first present a theoretical scheme for determining the excluded volumes of anisotropic particles. Also, the mean tangent diameters of anisotropic convex particles are formulated by the quantitative stereology. Subsequently, Monte Carlo simulations are demonstrated to numerically evaluate… More >

Amir Reza Ansari Dezfoli¹, Weng-Sing Hwang^1,2

CMC-Computers, Materials & Continua, Vol.49-50, No.1, pp. 1-11, 2015, DOI:10.3970/cmc.2015.049.001

Abstract Investigations of the microstructural evolution of Titanium (Ti) alloys during high temperature processes and heat treatment are attracting more attention due to wide variety of applications for such alloys. In most of these processes the Titanium alloys are subjected to fast heating or cooling rates. In this paper, Monte Carlo simulation is used to simulate the grain growth kinetics of Ti-6Al-4V alloy during fast heat treatment. Here, Monte Carlo simulation of grain growth is based on the Q-state Potts model. Our model is calibrated using the parabolic grain growth law, dⁿ-d₀ⁿ = kt, where the empirical constants are taken… More >

J. Joseph¹, Y. C. Lu ¹,

CMC-Computers, Materials & Continua, Vol.42, No.1, pp. 63-74, 2014, DOI:10.3970/cmc.2014.042.063

Abstract The super-long, vertically aligned carbon nanotubes (SL-VACNTs) are novel carbon nanomaterial produced from template-free synthesis. The mechanical responses of such material have been investigated by continuum finite element modeling and compared with experimental observations. The crushable foam model has been adequate in modeling the stress-strain curve and deformation of the SL-VACNTs under compression. SL-VACNTs are seen to exhibit transient elastic deformation at small displacement and then plastic deformation at large displacement. The deformation mostly occur at the position immediately beneath the compression platen (indenter face) due to the high stress/strain concentrations. More >

Anna Y. Matveeva¹, Helmut J. Böhm², Grygoriy Kravchenko², Ferrie W. J. van Hattum¹

CMC-Computers, Materials & Continua, Vol.42, No.1, pp. 1-23, 2014, DOI:10.3970/cmc.2014.042.001

Abstract This paper presents a comparison of different finite element approaches to modelling polymers reinforced with wavy, hollow fibres with the aim of predicting the effective elastic stiffness tensors of the composites. The waviness of the tubes is described by sinusoidal models with different amplitude-to-wavelength parameters. These volume elements are discretized by structured volume meshes onto which fibres in the form of independently meshed beam, shell or volume elements are superimposed. An embedded element technique is used to link the two sets of meshes. Reference solutions are obtained from conventional three-dimensional volume models of the same phase arrangements. Periodicity boundary conditions… More >

Xiangkui Zhou¹, Kai Wang¹, Zhifeng Xu¹, Qiang Wang², Guojian Li^1,, Jicheng He^1,

CMC-Computers, Materials & Continua, Vol.41, No.2, pp. 153-162, 2014, DOI:10.3970/cmc.2014.041.153

Abstract At present, the functionally gradient cemented carbide (FGCC) substrate with enrich cobalt on surface is mainly formed from medium grained WC grains. In order to further improve the properties of gradient cemented carbides, the ultrafine powder was chosen in this study and the functionally gradient cemented carbide with ultrafine grains was prepared by a two-step process, where the cemented carbide is first lower pressure pre-sintered and then subjected to a gradient sintering. The results show that it is possible to form gradient layer with enriched cobalt on surface by this method and also the grain growth can be inhibited by… More >