Shuren Zhou^1,2,*, Wenlong Liang^1,2, Junguo Li^1,2, Jeong-Uk Kim³

CMC-Computers, Materials & Continua, Vol.57, No.1, pp. 11-24, 2018, DOI:10.32604/cmc.2018.02617

Abstract Road traffic sign recognition is an important task in intelligent transportation system. Convolutional neural networks (CNNs) have achieved a breakthrough in computer vision tasks and made great success in traffic sign classification. In this paper, it presents a road traffic sign recognition algorithm based on a convolutional neural network. In natural scenes, traffic signs are disturbed by factors such as illumination, occlusion, missing and deformation, and the accuracy of recognition decreases, this paper proposes a model called Improved VGG (IVGG) inspired by VGG model. The IVGG model includes 9 layers, compared with the original VGG model, it is added max-pooling… More >

Yongli Tang¹, Huanhuan Lian¹, Zemao Zhao², Xixi Yan^1,*

CMC-Computers, Materials & Continua, Vol.56, No.2, pp. 339-352, 2018, DOI: 10.3970/cmc.2018.02965

Abstract With the widespread use of cloud computing technology, more and more users and enterprises decide to store their data in a cloud server by outsourcing. However, these huge amounts of data may contain personal privacy, business secrets and other sensitive information of the users and enterprises. Thus, at present, how to protect, retrieve, and legally use the sensitive information while preventing illegal accesses are security challenges of data storage in the cloud environment. A new proxy re-encryption with keyword search scheme is proposed in this paper in order to solve the problem of the low retrieval efficiency of the encrypted… More >

Taoyun Zhou^1,2, Baowang Lian¹, Siqing Yang^2,*, Yi Zhang¹, Yangyang Liu^1,3

CMC-Computers, Materials & Continua, Vol.56, No.2, pp. 225-245, 2018, DOI: 10.3970/cmc.2018.02671

Abstract For situations such as indoor and underground parking lots in which satellite signals are obstructed, GNSS cooperative positioning can be used to achieve high-precision positioning with the assistance of cooperative nodes. Here we study the cooperative positioning of two static nodes, node 1 is placed on the roof of the building and the satellite observation is ideal, node 2 is placed on the indoor windowsill where the occlusion situation is more serious, we mainly study how to locate node 2 with the assistance of node 1. Firstly, the two cooperative nodes are located with pseudo-range single point positioning, and the… More >

Yang Du¹, Zhaoxia Yin^1,2,*, Xinpeng Zhang³

CMC-Computers, Materials & Continua, Vol.55, No.3, pp. 495-507, 2018, DOI: 10.3970/cmc.2018.02440

Abstract This paper proposes a lossless and high payload data hiding scheme for JPEG images by histogram modification. The most in JPEG bitstream consists of a sequence of VLCs (variable length codes) and the appended bits. Each VLC has a corresponding RLV (run/length value) to record the AC/DC coefficients. To achieve lossless data hiding with high payload, we shift the histogram of VLCs and modify the DHT segment to embed data. Since we sort the histogram of VLCs in descending order, the filesize expansion is limited. The paper’s key contribution includes: Lossless data hiding, less filesize expansion in identical pay-load and… More >

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 179-201, 2015, DOI:10.3970/cmc.2015.047.179

Abstract Discontinuous smoothed particle hydrodynamics (DSPH) method based on traditional SPH method, which can be used to simulate discontinuous physics problems near interface or boundary. Previous works showed that DSPH method has a good application prospect [Xu et al, 2013], but further verification and improvement are demanded. In this paper, we investigate the accuracy of DSPH method by some numerical models. Moreover, to improve the accuracy of DSPH method, first order and second order multidimensional RDSPH methods are proposed by following the idea of restoring particle consistency in SPH (RSPH) method which has shown good results in the improvement of particle… More >

Huan Wang¹, Weifeng Yuan^2,3, Fei Jia²

CMC-Computers, Materials & Continua, Vol.47, No.1, pp. 31-43, 2015, DOI:10.3970/cmc.2015.047.031

Abstract Compared with dealing with a linear system, solving a nonlinear system equation in numerical simulation requires generally more CPU time since iterative approach is usually used in the latter. To cut down the computing cost, a direct way is to reduce the degree of freedoms (DOF) of the problem under investigation. However, this kind of treatment may result in poorer accuracy. In this manuscript, a macro element method is proposed to improve computational efficiency in large-scaled nonlinear analysis. When this concept is incorporated into finite element analysis (FEA), all the members in the linear zones of a structure can be… More >

Leiting Dong^1,2, Robert Haynes³, Satya N. Atluri²

CMC-Computers, Materials & Continua, Vol.45, No.1, pp. 1-16, 2015, DOI:10.3970/cmc.2015.045.001

Abstract In this study, we propose to approximate the a－n relation as well as the da/dn－∆K relation, in fatigue crack propagation, by using the Moving Least Squares (MLS) method. This simple approach can avoid the internal inconsistencies caused by the celebrated Paris’ power law approximation of the da/dn－∆K relation, as well as the error caused by a simple numerical differentiation of the noisy data for a－n measurements in standard fatigue tests. Efficient, accurate and automatic simulations of fatigue crack propagation can, in general, be realized by using the currently developed MLS law as the “fatigue engine” [da/dn versus ∆K], and using… More >

Yu Miao¹, Zhe Chen¹, Qiao Wang^1,2, Hongping Zhu¹

CMC-Computers, Materials & Continua, Vol.43, No.1, pp. 49-74, 2014, DOI:10.3970/cmc.2014.043.049

Abstract In this paper, an improved multi-domain model based on the hybrid boundary node method (Hybrid BNM) is proposed for mechanical analysis of 3D composites. The Hybrid BNM is a boundary type meshless method which based on the modified variational principle and the Moving Least Squares (MLS) approximation. The improved multi-domain model can reduce the total degrees of freedom (DOFs) compared with the conventional multi-domain solver. It is very suitable for the inclusion-based composites, especially for the composites when the inclusions are solid and totally embedded in the matrix domain. Numerical examples are presented to verify the improved multi-domain model and… More >

A. Ramachandra Murthy¹, G.S. Palani¹, Smitha Gopinath¹, V. Ramesh Kumar¹, Nagesh R. Iyer¹

CMC-Computers, Materials & Continua, Vol.37, No.2, pp. 77-96, 2013, DOI:10.3970/cmc.2013.037.077

Abstract This paper presents the development of an improved concrete damage model for projectile impact on concrete structural components. The improvement is in terms of reduction of input material parameters for nonlinear transient dynamic impact analysis by employing concrete damage model. The experimental data such as pressure vs volumetric strain, triaxial compression failure and pressure vs stress difference have been used for evaluation of the important parameters of concrete damage model. Various contact algorithms have been outlined briefly to model the interface between the projectile and target. The nonlinear explicit transient dynamic analysis has been carried out by using finite element… More >

J.M. Zhu¹, X.C. Wang¹, D. Wei², Y.H. Liu², B.Y. Xu²

CMC-Computers, Materials & Continua, Vol.22, No.3, pp. 261-274, 2011, DOI:10.3970/cmc.2011.022.261

Abstract The residual stiffness of concrete member after fire is a very important parameter of the load-bearing ability and seismic performance of fire-damaged concrete structures. It is also one of the most important criteria for repairing and reinforcing the fire-damaged concrete structures. Based on the equivalent elastic modulus method, improved segment model method and parameter inversion method developed in this paper, the residual stiffness of concrete members exposed to standard fire is calculated and the effects of fire duration, steel ratio and section size on the stiffness are also presented in detail. The results show that these three methods can easily… More >