Muhammad Haroon Aftab¹, Kamel Jebreen^2,*, Mohammad Issa Sowaity³, Muhammad Hussain⁴

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 1225-1236, 2022, DOI:10.32604/cmc.2022.029009

Abstract In this article, we study different molecular structures such as Polythiophene network, for and , Orthosilicate (Nesosilicate) , Pyrosilicates (Sorosilicates) , Chain silicates (Pyroxenes), and Cyclic silicates (Ring Silicates) for their cardinalities, chromatic numbers, graph variations, eigenvalues obtained from the adjacency matrices which are square matrices in order and their corresponding characteristics polynomials. We convert the general structures of these chemical networks in to mathematical graphical structures. We transform the molecular structures of these chemical networks which are mentioned above, into a simple and undirected planar graph and sketch them with various techniques of mathematics. The matrices obtained from these… More >

Hafiz Abid Mahmood Malik^*

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.3, pp. 1737-1750, 2022, DOI:10.32604/cmes.2022.018015

Abstract To discover and identify the influential nodes in any complex network has been an important issue. It is a significant factor in order to control over the network. Through control on a network, any information can be spread and stopped in a short span of time. Both targets can be achieved, since network of information can be extended and as well destroyed. So, information spread and community formation have become one of the most crucial issues in the world of SNA (Social Network Analysis). In this work, the complex network of twitter social network has been formalized and results are… More >

Jianwei Zhang¹, Ze Qin¹, Shunfeng Wang^{1, *}

Journal of Cyber Security, Vol.2, No.1, pp. 25-36, 2020, DOI:10.32604/jcs.2020.06429

Abstract Digital images have been applied to various areas such as evidence in courts. However, it always suffers from noise by criminals. This type of computer network security has become a hot issue that can’t be ignored. In this paper, we focus on noise removal so as to provide guarantees for computer network security. Firstly, we introduce a well-known denoising method called Expected Patch Log Likelihood (EPLL) with Gaussian Mixture Model as its prior. This method achieves exciting results in noise removal. However, there remain problems to be solved such as preserving the edge and meaningful details in image denoising, cause… More >

A.N. Guz¹, V.V. Zozulya²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.8, No.4, pp. 151-156, 2008, DOI:10.3970/icces.2008.008.151

Abstract The contact interaction of opposite faces of cracks in 2-D and 3-D solid is studied. The case of a normal time-harmonic wave loading is studied in more details. The distribution of stress intensity factors as functions of the wave number is investigated. The results are compared with those obtained for cracks without allowance for the contact interaction. More >

Zai You Yan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.13, No.2, pp. 81-90, 2006, DOI:10.3970/cmes.2006.013.081

Abstract Boundary element method in acoustics for Neumann boundary condition problems including sharp edges & corners is investigated. In previous acoustic boundary element method, acoustic pressure and normal velocity are the two variables at sharp edges & corners. However, the normal velocity at sharp edges & corners is discontinuous due to the indefinite normal vector. To avoid the indefinite normal vector and the discontinuous normal velocity at sharp edges & corners, normal vector of elemental node is defined and applied in the numerical implementation. Then the normal velocity is transformed to velocity which is unique even at sharp edges & corners.… More >

W. Attaporn¹, H. Koguchi²

CMES-Computer Modeling in Engineering & Sciences, Vol.39, No.3, pp. 237-262, 2009, DOI:10.3970/cmes.2009.039.237

Abstract In the present study, a stress singularity field along free edges meeting at a corner in a three-dimensional joint structure is investigated. The order of stress singularity is determined using an eigen analysis based on a finite element method. Intensities of stress singularity not only at the corner but also along the free edge of interface are determined directly without any post-processing by a new FEM formulation referred to as a three-dimensional enriched FEM. Result in the present analysis is also compared with that in another numerical method. It was slightly larger than the intensity of stress singularity, which was… More >

T. Kar, M.L. Munjal¹

CMES-Computer Modeling in Engineering & Sciences, Vol.27, No.1&2, pp. 37-48, 2008, DOI:10.3970/cmes.2008.027.037

Abstract In the present work, a wedge structure made of absorbing panels has been analyzed by making use of the matrizant analysis with the help of the Boundary-Condition-Transfer (BCT) algorithm. The rectangular panel wedge, as it is called in this manuscript, is simple in geometry. The theoretical model, based on the plane wave acoustical coupling between multiple interacting ducts of variable cross sectional area, is applied to predict the pressure reflection coefficient of the present wedge configuration. Bulk reaction and hence wave propagation in the wedge material has been assumed in the proposed model. An asymptotic solution using the Peano-Baker series… More >

F. De Rosa¹, A. Esposito¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.1, pp. 107-128, 2012, DOI:10.3970/fdmp.2011.008.107

Abstract An investigation was conducted to evaluate the feasibility and the performance of an electrically heated composite leading edge for aircraft anti-icing applications. A prototype was designed, manufactured and equipped with a High Temperature composite leading edge with embedded Ni alloy resistance fed by a DC power supply unit. Running wet and fully evaporative functional modes have been verified both analytically and experimentally with reasonable agreement. A room temperature thermal endurance test has been run for 10⁴ cycles aiming to preliminary verify the integrity of the composite laminate after the imposed thermal stress. The EHCLE system (Electrical Heated Composite Leading Edge)… More >

Chih-Ping Wu, Ruei-Yong Jiang

CMC-Computers, Materials & Continua, Vol.46, No.1, pp. 17-56, 2015, DOI:10.3970/cmc.2015.046.017

Abstract An asymptotic meshless method using the differential reproducing kernel (DRK) interpolation and multiple time scale methods is developed for the three-dimensional (3D) free vibration analysis of sandwich functionally graded material (FGM) circular hollow cylinders with combinations of simply-supported and clamped edge conditions. In the formulation, we perform the mathematical processes of nondimensionalization, asymptotic expansion and successive integration to obtain recurrent sets of motion equations for various order problems. Classical shell theory (CST) is derived as a first-order approximation of the 3D elasticity theory, and the motion equations for higher-order problems retain the same differential operators as those of CST, although… More >