Wajaree Weera¹, Zulqurnain Sabir², Muhammad Asif Zahoor Raja³, Sakda Noinang⁴, Thongchai Botmart^1,*

CMC-Computers, Materials & Continua, Vol.73, No.3, pp. 4833-4849, 2022, DOI:10.32604/cmc.2022.030888

Abstract The purpose of this research is to construct an integrated neuro swarming scheme using the procedures of the artificial neural networks (ANNs) with the use of global search particle swarm optimization (PSO) along with the competent local search interior-point programming (IPP) called as ANN-PSOIPP. The proposed computational scheme is implemented for the numerical simulations of the third order nonlinear delay differential Emden-Fowler model (TON-DD-EFM). The TON-DD-EFM is based on two types along with the particulars of shape factor, delayed terms, and singular points. A merit function is performed using the optimization of PSOIPP to find the solutions to the TON-DD-EFM.… More >

Chao Ma, Yunkai Gao^*, Yuexing Duan, Zhe Liu

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.2, pp. 715-738, 2021, DOI:10.32604/cmes.2021.011187

Abstract Stress-based topology optimization is one of the most concerns of structural optimization and receives much attention in a wide range of engineering designs. To solve the inherent issues of stress-based topology optimization, many schemes are added to the conventional bi-directional evolutionary structural optimization (BESO) method in the previous studies. However, these schemes degrade the generality of BESO and increase the computational cost. This study proposes an improved topology optimization method for the continuum structures considering stress minimization in the framework of the conventional BESO method. A global stress measure constructed by p-norm function is treated as the objective function. To… More >

Yuming Chu¹, Naila Rafiq², Mudassir Shams^3,*, Saima Akram⁴, Nazir Ahmad Mir³, Humaira Kalsoom⁵

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 275-290, 2021, DOI:10.32604/cmc.2020.011907

Abstract In this article, we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations. Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine. Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes, numerical experiments and CPU time-methodology. Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous… More >

Jinlan Xu^*, Ningning Sun, Gang Xu

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 627-642, 2020, DOI:10.32604/cmes.2020.010341

Abstract This paper presents a novel approximating method to construct highprecision single-patch representation of B-spline surface from a multi-patch representation for isogeometric applications. In isogeometric analysis, multi-patch structure is not easy to achieve high continuity between neighboring patches which will reduce the advantage of isogeometric analysis in a sense. The proposed method can achieve high continuity at surface stitching region with low geometric error, and this technique exploits constructing the approximate surface with several control points are from original surfaces, which guarantees the local feature of the surface can be well-preserved with high precision. With the proposed approximating method, isogeometric analysis… More >

Q.W. Ma

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.1, pp. 15-16, 2011, DOI:10.3970/icces.2011.019.015

Abstract Over the past several years, the research group led by the author has extended the MPLG (Meshless Local Petrov-Galerkin) method developed by Prof. Atluri and his group to model nonlinear water waves; and then made further development to produce a method called MLPG_R (Meshless Local Petrov-Galerkin method based on Rankine source solution) method. In order to improve the computational efficiency of the method for modelling nonlinear water waves, several techniques have been developed. They include (1) introduction of a weak form of governing equation that does not contain derivatives of unknown functions; (2) a new meshless interpolation method of a… More >

M.R. Moosavi¹, A. Khelil¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.4, pp. 211-238, 2008, DOI:10.3970/icces.2008.005.211

Abstract In this paper, a combined formulation of the Finite Volume Method (FVM) and the Meshless Local Petrov-Galerkin (MLPG) is investigated to solve elasto-static problem. Accuracy and computational efficiency study between the combined formulation and the Finite Element Method (FEM) is presented. Some problems of beam under various loading and boundary conditions are analyzed by the proposed method, and the numerical results are compared with analytical solution and result of other numerical method which is obtained by well-known FEM software ABAQUS. The advantages of the FVM combined MLPG (FVMLPG) with respect to the FEM are illustrated. Higher accuracies and computational efficiencies… More >

Cong Xie¹, Guangyu Shi^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.6, pp. 397-427, 2015, DOI:10.3970/cmes.2015.108.397

Abstract The static and dynamic thermoelastic analyses of the beams made of functionally graded materials (FGMs) are presented in this paper. Based on the refined third-order shear deformation beam theory proposed by the senior author and the variational principle, the governing equations of FG beams are deduced. The influence of temperature on Young’s modulus and coefficients of thermal expansion is taken into account when FG beams are subjected to thermal loading. The resulting governing equations are a system of the eighth-order differential equations in terms of displacement variables, and the thermoelastic coupling is included in the equations. An accurate and reliable… More >

V. Sladek¹, J. Sladek¹, Ch. Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.3, pp. 243-264, 2010, DOI:10.3970/cmes.2010.063.243

Abstract The paper deals with diminishing the prolongation of the computational time due to procedural evaluation of the shape functions and their derivatives in weak formulations implemented with meshless approximations. The proposed numerical techniques are applied to problems of stationary heat conduction in functionally graded media. Besides the investigation of the computational efficiency also the accuracy and convergence study are performed in numerical tests. More >

Peter Lucas¹, Alexander H. van Zuijlen¹, Hester Bijl¹

CMES-Computer Modeling in Engineering & Sciences, Vol.41, No.2, pp. 147-176, 2009, DOI:10.3970/cmes.2009.041.147

Abstract Mesh adaptation is a fairly established tool to obtain numerically accurate solutions for flow problems. Computational efficiency is, however, not always guaranteed for the adaptation strategies found in literature. Typically excessive mesh growth diminishes the potential efficiency gain. This paper, therefore, extends the strategy proposed by [Aftosmis and Berger (2002)] to compute the refinement threshold. The extended strategy computes the refinement threshold based on a user desired number of grid cells and adaptations, thereby ensuring high computational efficiency. Because our main interest is flow around wind turbines, the adaptation strategy has been optimized for flow around wind turbine airfoils. The… More >

Jinlan Xu¹, Ningning Sun¹, Laixin Shu¹, Timon Rabczuk², Gang Xu^1,*

CMC-Computers, Materials & Continua, Vol.60, No.2, pp. 615-632, 2019, DOI:10.32604/cmc.2019.04464

Abstract Trimming techniques are efficient ways to generate complex geometries in Computer-Aided Design (CAD). In this paper, an improved integration for trimmed geometries in isogeometric analysis (IGA) is proposed. The proposed method can improve the accuracy of the approximation and the condition number of the stiffness matrix. In addition, comparing to the traditional approaches, the trimming techniques can reduce the number of the integration elements with much fewer integration points, which improves the computational efficiency significantly. Several examples are illustrated to show the effectiveness of the proposed approach. More >