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arXiv cs/0104018math.NAcs.CEcs.NA
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若干基于径向基函数的新型域型和边界型数值离散格式

Several new domain-type and boundary-type numerical discretization schemes with radial basis function

W. Chen

AI总结:

本文提出多种基于径向基函数的对称、无网格、免积分的边界型和域型数值离散格式,包括BKM、BPM、MKM和FKM,显著降低边界附近误差,并推荐非奇异高阶基本解作为RBF。

摘要:

本文关注若干新颖的基于径向基函数(RBF)的偏微分方程数值离散格式。对于边界型方法,我们推导了间接和直接对称边界结点法(BKM)。两种方法得到的插值矩阵无论边界几何和条件如何都是对称的。特别地,直接BKM使用实际的物理变量而非展开系数,使其在与边界元法的竞争中极具优势。另一方面,基于多重互易原理,我们发明了基于RBF的边界粒子法(BPM),用于一般非齐次问题而无需使用内部节点。还发展了直接和对称的BPM格式。对于域型RBF离散格式,通过使用格林积分,我们发展了一种新的Hermite RBF格式,称为修正Kansa方法(MKM),它与对称Hermite RBF格式的不同之处在于MKM在同一组边界节点上同时离散控制方程和边界条件。MKM的局部样条版本被称为有限结点法(FKM)。MKM和FKM都显著减少了边界附近节点的计算误差。此外,强烈推荐使用非奇异的高阶基本解或一般解作为域型方法和与BKM相关的特解双重互易法逼近中的RBF。需要强调的是,上述所有边界型和域型离散方法都是对称的、无网格的且无需积分的。基于样条的格式将产生理想的对称稀疏带状插值矩阵。在附录中,我们提出了一种Hermite格式以消除RBF几何建模和成像中的边缘效应。

英文摘要:

This paper is concerned with a few novel RBF-based numerical schemes discretizing partial differential equations. For boundary-type methods, we derive the indirect and direct symmetric boundary knot methods (BKM). The resulting interpolation matrix of both is always symmetric irrespective of boundary geometry and conditions. In particular, the direct BKM applies the practical physical variables rather than expansion coefficients and becomes very competitive to the boundary element method. On the other hand, based on the multiple reciprocity principle, we invent the RBF-based boundary particle method (BPM) for general inhomogeneous problems without a need using inner nodes. The direct and symmetric BPM schemes are also developed. For domain-type RBF discretization schemes, by using the Green integral we develop a new Hermite RBF scheme called as the modified Kansa method (MKM), which differs from the symmetric Hermite RBF scheme in that the MKM discretizes both governing equation and boundary conditions on the same boundary nodes. The local spline version of the MKM is named as the finite knot method (FKM). Both MKM and FKM significantly reduce calculation errors at nodes adjacent to boundary. In addition, the nonsingular high-order fundamental or general solution is strongly recommended as the RBF in the domain-type methods and dual reciprocity method approximation of particular solution relating to the BKM. It is stressed that all the above discretization methods of boundary-type and domain-type are symmetric, meshless, and integration-free. The spline-based schemes will produce desirable symmetric sparse banded interpolation matrix. In appendix, we present a Hermite scheme to eliminate edge effect on the RBF geometric modeling and imaging.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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