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81.
王家正 《应用数学与计算数学学报》2006,20(2):77-82
Stieltjes型分叉连分式在有理插值问题中有着重要的地位,它通过定义反差商和混合反差商构造给定结点上的二元有理函数,我们将Stieltjes型分叉连分式与二元多项式结合起来,构造Stieltje- Newton型有理插值函数,通过定义差商和混合反差商,建立递推算法,构造的Stieltjes-Newton型有理插值函数满足有理插值问题中所给的插值条件,并给出了插值的特征定理及其证明,最后给出的数值例子,验证了所给算法的有效性. 相似文献
82.
A.F. Nindjin 《Journal of Mathematical Analysis and Applications》2008,340(1):340-357
Our investigation concerns the three-dimensional delayed continuous time dynamical system which models a predator-prey food chain. This model is based on the Holling-type II and a Leslie-Gower modified functional response. This model can be considered as a first step towards a tritrophic model (of Leslie-Gower and Holling-Tanner type) with inverse trophic relation and time delay. That is when a certain species that is usually eaten can consume immature predators. It is proved that the system is uniformly persistent under some appropriate conditions. By constructing a proper Lyapunov function, we obtain a sufficient condition for global stability of the positive equilibrium. 相似文献
83.
研究了B值鞅Hardy空间与BMO空间的实内插,并利用所得结果,讨论了鞅Hardy空间的内插空间的共轭问题。 相似文献
84.
85.
梁军 《数学的实践与认识》2016,(17):229-235
采用重心Lagrange插值配点法计算了二维Poisson方程.采用重心Lagrange插值法构造近似函数,由配点法离散Poisson方程及其边界条件.数值算例表明方法具有理论简单、计算精度高的特点. 相似文献
86.
Constrained moving least‐squares immersed boundary method for fluid‐structure interaction analysis 下载免费PDF全文
A numerical method is presented for the analysis of interactions of inviscid and compressible flows with arbitrarily shaped stationary or moving rigid solids. The fluid equations are solved on a fixed rectangular Cartesian grid by using a higher‐order finite difference method based on the fifth‐order WENO scheme. A constrained moving least‐squares sharp interface method is proposed to enforce the Neumann‐type boundary conditions on the fluid‐solid interface by using a penalty term, while the Dirichlet boundary conditions are directly enforced. The solution of the fluid flow and the solid motion equations is advanced in time by staggerly using, respectively, the third‐order Runge‐Kutta and the implicit Newmark integration schemes. The stability and the robustness of the proposed method have been demonstrated by analyzing 5 challenging problems. For these problems, the numerical results have been found to agree well with their analytical and numerical solutions available in the literature. Effects of the support domain size and values assigned to the penalty parameter on the stability and the accuracy of the present method are also discussed. 相似文献
87.
In this paper we study spectral sets which are unions of finitely many intervals in R. We show that any spectrum associated with such a spectral set Ω is periodic, with the period an integral multiple of the measure of Ω. As a consequence we get a structure theorem for such spectral sets and observe that the generic case is that of the equal interval case. 相似文献
88.
This article presents the study of singularly perturbed parabolic reaction–diffusion problems with boundary layers. To solve these problems, we use a modified backward Euler finite difference scheme on layer adapted nonuniform meshes at each time level. The nonuniform meshes are obtained by equidistribution of a positive monitor function, which involves the second-order spatial derivative of the singular component of the solution. The equidistributing monitor function at each time level allows us to use this technique to non-linear parabolic problems. The truncation error and the stability analysis are obtained. Parameter–uniform error estimates are derived for the numerical solution. To support the theoretical results, numerical experiments are carried out. 相似文献
89.
Divergence-free wavelets are successfully applied to numerical solutions of Navier-Stokes equation and to analysis of incompressible
flows. They closely depend on a pair of one-dimensional wavelets with some differential relations. In this paper, we point
out some restrictions of those wavelets and study scaling functions with the differential relation; Wavelets and their duals
are discussed; In addition to the differential relation, we are particularly interested in a class of examples with the interpolatory
property; It turns out there is a connection between our examples and Micchelli’s work. 相似文献
90.