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991.
Mustafa Gülsu Mehmet Sezer 《Numerical Methods for Partial Differential Equations》2011,27(6):1628-1638
A numerical method based on the Taylor polynomials is introduced in this article for the approximate solution of the pantograph equations with constant and variable coefficients. Some numerical examples, which consist of the initial conditions, are given to show the properties of the method. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27:1628–1638, 2011 相似文献
992.
目标规划中权系数的几何意义 总被引:1,自引:0,他引:1
本用平面仿射坐标的观点,解释了目标规划中权系数的几何意义,借助于坐标变换,可改进图解法的效果。 相似文献
993.
In this paper, we use the laminar viscous flow in a lid‐driven cavity as an example to describe and verify a numerical scheme for non‐linear partial differential equations. The proposed scheme combines a new analytical method for strongly non‐linear problems, namely the homotopy analysis method, with the multigrid techniques. A family of formulas at different orders is given. At the lowest order, the current approach is the same as the traditional multigrid methods. However, our high‐order scheme needs a fewer number of iterations and less CPU time than the classical ones. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
994.
C. Vanneste 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,23(3):391-404
This paper presents an extension to electromagnetic fields of the wave automaton, which was introduced in recent years for
describing wave propagation in inhomogeneous media. Using elementary processes obeying a discrete Huygens' principle and satisfying
fundamental symmetries such as time reversal and reciprocity, this new wave automaton is capable of modeling Maxwell's equations
in 3+1 dimensions. It supplements the methods that were developed early for scalar and spinor fields.
Received 19 July 2001 相似文献
995.
提出了非线性绝对值方程组(AVE)问题解的存在性和唯一性的一个充分条件,构建了数值求解方程组的类超松弛迭代方法,并证明其收敛性.数值算例表明该迭代方法是非常有效的. 相似文献
996.
997.
We study an optimal control problem with quadratic objective functional for the three dimensional Navier-Stokes-Voigt equations in bounded domains. We show the existence of optimal solutions, the necessary optimality conditions and the sufficient optimality conditions. The second-order optimality conditions obtained in the article seem to be optimal. 相似文献
998.
In this work, the residual‐type posteriori error estimates of stabilized finite volume method are studied for the steady Stokes problem based on two local Gauss integrations. By using the residuals between the source term and numerical solutions, the computable global upper and local lower bounds for the errors of velocity in H1 norm and pressure in L2 norm are derived. Furthermore, a global upper bound of u ? uh in L2‐norm is also derived. Finally, some numerical experiments are provided to verify the performances of the established error estimators. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
Velinda Calvert Somayeh Mashayekhi Mohsen Razzaghi 《Mathematical Methods in the Applied Sciences》2016,39(5):1268-1284
In this paper, a numerical method for solving Lane‐Emden type equations, which are nonlinear ordinary differential equations on the semi‐infinite domain, is presented. The method is based upon the modified rational Bernoulli functions; these functions are first introduced. Operational matrices of derivative and product of modified rational Bernoulli functions are then given and are utilized to reduce the solution of the Lane‐Emden type equations to a system of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of the technique. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Serhii V. Gryshchuk Sergiy A. Plaksa 《Mathematical Methods in the Applied Sciences》2016,39(11):2939-2952
We consider a commutative algebra over the field of complex numbers with a basis {e1,e2} satisfying the conditions , . Let D be a bounded domain in the Cartesian plane xOy and Dζ={xe1+ye2:(x,y)∈D}. Components of every monogenic function Φ(xe1+ye2) = U1(x,y)e1+U2(x,y)ie1+U3(x,y)e2+U4(x,y)ie2 having the classic derivative in Dζ are biharmonic functions in D, that is, Δ2Uj(x,y) = 0 for j = 1,2,3,4. We consider a Schwarz‐type boundary value problem for monogenic functions in a simply connected domain Dζ. This problem is associated with the following biharmonic problem: to find a biharmonic function V(x,y) in the domain D when boundary values of its partial derivatives ?V/?x, ?V/?y are given on the boundary ?D. Using a hypercomplex analog of the Cauchy‐type integral, we reduce the mentioned Schwarz‐type boundary value problem to a system of integral equations on the real axes and establish sufficient conditions under which this system has the Fredholm property. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献