Zhiguo Wang^*, Fangqing Gao, Fei Liu

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.1, pp. 343-355, 2023, DOI:10.32604/cmes.2022.020569 - 24 August 2022

Abstract In this paper, an improved high-order model-free adaptive iterative control (IHOMFAILC) method for a class of nonlinear discrete-time systems is proposed based on the compact format dynamic linearization method. This method adds the differential of tracking error in the criteria function to compensate for the effect of the random disturbance. Meanwhile, a high-order estimation algorithm is used to estimate the value of pseudo partial derivative (PPD), that is, the current value of PPD is updated by that of previous iterations. Thus the rapid convergence of the maximum tracking error is not limited by the initial More >

V. Magesh^1,*, N. Duraipandian²

Intelligent Automation & Soft Computing, Vol.31, No.3, pp. 1499-1510, 2022, DOI:10.32604/iasc.2022.020552 - 09 October 2021

Abstract The current research paper discusses the implementation of higher order-matched filter design using odd and even phase processes for efficient area and time delay reduction. Matched filters are widely used tools in the recognition of specified task. When higher order taps are implemented upon the transposed form of matched filters, it can enhance the image recognition application and its performance in terms of identification and accuracy. The proposed method i.e., odd and even phases’ process of FIR filter can reduce the number of multipliers and adders, used in existing system. The main advantage of using… More >

Luciano Pereira da Silva^1,*, Bruno Benato Rutyna¹, Aline Roberta Santos Righi², Marcio Augusto Villela Pinto³

CMES-Computer Modeling in Engineering & Sciences, Vol.128, No.2, pp. 699-715, 2021, DOI:10.32604/cmes.2021.014239 - 22 July 2021

Abstract In this article, we improve the order of precision of the two-dimensional Poisson equation by combining extrapolation techniques with high order schemes. The high order solutions obtained traditionally generate non-sparse matrices and the calculation time is very high. We can obtain sparse matrices by applying compact schemes. In this article, we compare compact and exponential finite difference schemes of fourth order. The numerical solutions are calculated in quadruple precision (Real * 16 or extended precision) in FORTRAN language, and iteratively obtained until reaching the round-off error magnitude around 1.0E −32. This procedure is performed to ensure More >

A. I. Asnor¹, S. A. M. Yatim¹, Z. B. Ibrahim², N. Zainuddin³

CMC-Computers, Materials & Continua, Vol.67, No.1, pp. 1253-1267, 2021, DOI:10.32604/cmc.2021.014781 - 12 January 2021

Abstract Many initial value problems are difficult to be solved using ordinary, explicit step-by-step methods because most of these problems are considered stiff. Certain implicit methods, however, are capable of solving stiff ordinary differential equations (ODEs) usually found in most applied problems. This study aims to develop a new numerical method, namely the high order variable step variable order block backward differentiation formula (VSVO-HOBBDF) for the main purpose of approximating the solutions of third order ODEs. The computational work of the VSVO-HOBBDF method was carried out using the strategy of varying the step size and order… More >

S. M. Arifuzzaman^1,* , Md. Shakhaoath Khan² , Khan Enaet Hossain¹ , Md. Sirajul Islam³ , Sonia Akter³, Raju Roy¹

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-12, 2017, DOI:10.5098/hmt.9.5

Abstract Present study concerned with the theoretical work with numerical investigation of MHD transient naturally convective and higher order chemically reactive viscoelastic fluid with nano-particle flow through a vertical porous stretching sheet with the effects of heat generation and radiation absorption. A boundary layer approximation is carried out to develop a flow model representing time dependent momentum, energy, and concentration equations. The governing model equations in partial differential equations (PDEs) form were transformed into a set of nonlinear ordinary differential equation (ODEs) by using non-similar technique. Explicit Finite Difference Method (EFDM) was employed by implementing an… More >

F. Yang¹, C.L. Fu², X.X. Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.100, No.1, pp. 19-29, 2014, DOI:10.3970/cmes.2014.100.019

Abstract Numerical differentiation is a classical ill-posed problem. The generalized Tikhonov regularization method is proposed to solve this problem. The error estimates are obtained for a priori and a posteriori parameter choice rules, respectively. Numerical examples are presented to illustrate the validity and effectiveness of this method. More >

Tae Soo Kim¹, Pa Ul Mun¹, Myung Kuk Lee¹, Jae Soo Kim^1,2

The International Conference on Computational & Experimental Engineering and Sciences, Vol.10, No.2, pp. 65-70, 2009, DOI:10.3970/icces.2009.010.065

Abstract This article has no abstract. More >

M. Dumbser¹, D.S. Balsara²

CMES-Computer Modeling in Engineering & Sciences, Vol.54, No.3, pp. 301-334, 2009, DOI:10.3970/cmes.2009.054.301

Abstract In this article we use the new, unified framework of high order one-step P_NP_M schemes recently proposed for inviscid hyperbolic conservation laws by Dumbser, Balsara, Toro, and Munz (2008) in order to solve the viscous and resistive magnetohydrodynamics (MHD) equations in two and three space dimensions on unstructured triangular and tetrahedral meshes. The P_NP_M framework uses piecewise polynomials of degree N to represent data in each cell and piecewise polynomials of degree M ≥ N to compute the fluxes and source terms. This new general machinery contains usual high order finite volume schemes (N = 0) and discontinuous… More >

Y.M. Zhang¹, Y. Gu¹, J.T. Chen²

CMES-Computer Modeling in Engineering & Sciences, Vol.45, No.3, pp. 227-248, 2009, DOI:10.3970/cmes.2009.045.227

Abstract The accurate evaluation of nearly singular integrals is one of the major concerned problems in the boundary element method (BEM). Although the current methods have achieved great progress, it is often possible only for problems defined in the simplest geometrical domains when the nearly singular integrals need to be calculated. However, engineering processes occur mostly in complex geometrical domains, and always, involve nonlinearities of the unknown variables and its derivatives. Therefore, effective methods of dealing with nearly singular integrals for such practical problems are necessary and need to be further investigated. In this paper, a More >

Yueting Zhou¹, Xing Li², Dehao Yu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.43, No.3, pp. 191-222, 2009, DOI:10.3970/cmes.2009.043.191

Abstract The transient response of an orthotropic functionally graded strip with a partially insulated crack under convective heat transfer supply is considered. It is modeled there exists thermal resistant in the heat conduction through the crack region. The mixed boundary value problems of the temperature field and displacement field are reduced to a system of singular integral equations in Laplace domain. The expressions with high order asymptotic terms for the singular integral kernel are considered to improve the accuracy and efficiency. The numerical results present the effect of the material nonhomogeneous parameters, the orthotropic parameters and More >