Jindan Lyu¹, Longdi Cheng^1,*, Bugao Xu^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.2, pp. 737-751, 2021, DOI:10.32604/cmes.2021.015153

Abstract Compact spinning with pneumatic grooves is a spinning process to gather fibers by blended actions of airflow and mechanical forces. Modified from the ring spinning system, the lateral compact spinning with pneumatic grooves can improve yarn appearance and properties due to generated additional twists. In this study, we investigated additional twists of the lateral compact spinning with pneumatic grooves via a finite element (FE) method. An elastic thin rod was used to model a fiber to simulate its dynamic deformation in the three-dimensional space, and the space bar unit was used to simplify the fiber model for the dynamic analysis.… More >

Anh Tuan Hoang¹, Xuan Phuong Nguyen², Osamah Ibrahim Khalaf³, Thi Xuan Tran⁴, Minh Quang Chau⁵, Thi Minh Hao Dong², Duong Nam Nguyen^6,*

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 1129-1145, 2021, DOI:10.32604/cmc.2021.015349

Abstract The type of technology used to strengthen the surface structure of machine parts, typically by carbon-permeation, has made a great contribution to the mechanical engineering industry because of its outstanding advantages in corrosion resistance and enhanced mechanical and physical properties. Furthermore, carbon permeation is considered as an optimal method of heat treatment through the diffusion of carbon atoms into the surface of alloy steel. This study presented research results on the thermodynamic calculation and simulation of the carbon permeability process. Applying Fick’s law, the paper calculated the distribution of carbon concentration in the alloy steel after it is absorbed from… More >

Weidong Lei¹, Hai Zhou^1,*, Hongjun Li², Rui Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.2, pp. 577-597, 2021, DOI:10.32604/cmes.2021.011857

Abstract In order to simulate the propagation process of subway vibration of parallel tunnels in semi-infinite rocks or soils, time domain boundary element method (TD-BEM) formulation for analyzing the dynamic response of twin-parallel circular tunnels in an elastic semi-infinite medium is developed in this paper. The time domain boundary integral equations of displacement and stress for the elastodynamic problem are presented based on Betti’s reciprocal work theorem, ignoring contributions from initial conditions and body forces. In the process of establishing time domain boundary integral equations, some virtual boundaries are constructed between finite boundaries and the free boundary to form a boundary… More >

Yue Li¹, Guangquan Xu^2,3, Hequn Xian^1,*, Longlong Rao³, Jiangang Shi^4,*

Intelligent Automation & Soft Computing, Vol.25, No.3, pp. 637-647, 2019, DOI:10.31209/2019.100000118

Abstract In order to prevent the spread of Android malware and protect privacy information from being compromised, this study proposes a novel multidimensional hybrid features extraction and analysis method for Android malware detection. This method is based primarily on a multidimensional hybrid features vector by extracting the information of permission requests, API calls, and runtime behaviors. The innovation of this study is to extract greater amounts of static and dynamic features information and combine them, that renders the features vector for training completer and more comprehensive. In addition, the feature selection algorithm is used to further optimize the extracted information to… More >

Jiaye Pan¹, Yi Zhuang^{1, *}, Xinwen Hu^{1, 2}, Wenbing Zhao³

CMC-Computers, Materials & Continua, Vol.64, No.1, pp. 607-622, 2020, DOI:10.32604/cmc.2020.09853

Abstract Nowadays cloud architecture is widely applied on the internet. New malware aiming at the privacy data stealing or crypto currency mining is threatening the security of cloud platforms. In view of the problems with existing application behavior monitoring methods such as coarse-grained analysis, high performance overhead and lack of applicability, this paper proposes a new fine-grained binary program monitoring and analysis method based on multiple system level components, which is used to detect the possible privacy leakage of applications installed on cloud platforms. It can be used online in cloud platform environments for fine-grained automated analysis of target programs, ensuring… More >

Siyang Piao¹, Huajiang Ouyang^{1, 2}, Yahui Zhang^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.2, pp. 571-591, 2020, DOI: 10.32604/cmes.2020.08789

Abstract A beam approximation method for dynamic analysis of launch vehicles modelled as stiffened cylindrical shells is proposed. Firstly, an initial beam model of the stiffened cylindrical shell is established based on the cross-sectional area equivalence principle that represents the shell skin and its longitudinal ribs as a beam with annular cross-section, and the circumferential ribs as lumped masses at the nodes of the beam elements. Then, a fine finite element model (FE model) of the stiffened cylindrical shell is constructed and a modal analysis is carried out. Finally, the initial beam model is improved through model updating against the natural… More >

Shichao Ma^{1, 2, *}, Xin Ning^{1, 2, *}, Liang Wang³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 49-59, 2020, DOI:10.32604/cmes.2020.06911

Abstract Friction systems are a kind of typical non-linear dynamical systems in the actual engineering and often generate abundant dynamics phenomena. Because of non-smooth characteristics, it is difficult to handle these systems by conventional analysis methods directly. At the same time, random perturbation often affects friction systems and makes these systems more complicated. In this context, we investigate the steady-state stochastic responses and stochastic P-bifurcation of friction systems under random excitations in this paper. And in order to retain the non-smooth of friction system, the generalized cell mapping (GCM) method is first used to the original stochastic friction systems without any… More >

Wei LIU, Jiacong YIN, Pu CHEN, Xianyue SU

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.017.127

Abstract In this paper, parametric modeling technique is employed to fast build the three-dimensional finite element shell model of a preliminarily designed large composite wind turbine blade, which is subsequently used in the dynamic analysis and static elastic aeroelastic stability analysis of the blade. In the dynamic analysis, natural frequencies and corresponding modal shapes are obtained for the blade in the case of being still as well as being rotating with rated revolution. For the rotating blade, the stress stiffening effect and spin-softening effect due to the centrifugal forces are taken into account. The static elastic aeroelastic stability analysis, i.e. buckling… More >

Nengguang Liu, Wei Gao, Chongmin Song, Nong Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.3, pp. 83-84, 2011, DOI:10.3970/icces.2011.020.083

Abstract This paper presents the probabilistic dynamic analysis of vehicle-bridge interaction systems. The bridge's and vehicle's parameters are considered as random variables as well as the road surface roughness is modeled as random process. A quarter-car model is used to represent a moving vehicle and the bridge is treated as an Euler-Bernoulli beam. From the equation of motion for the vehicle-bridge coupling system, the expressions for mean value and standard deviation of bridge response are developed by using the random variable's functional moment method. The effects of the individual system parameters and the road surface roughness on the bridge response are… More >

Z. Bittnar, L. Vrablik, M. Polak, V. Kristek¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.13, No.2, pp. 43-48, 2009, DOI:10.3970/icces.2009.013.043

Abstract Detail structural and dynamic analysis of concrete suspended bridge structure in Prague which was assessed because of severe damages of parapets and expansion joints is presented. Measured and calculated results are compared and approaches to repairing and stiffening are also recommended. More >