TY - EJOU AU - Jin, Xiaozhong AU - Li, Gang AU - Aluru, N. R. TI - On the Equivalence Between Least-Squares and Kernel Approximations in Meshless Methods T2 - Computer Modeling in Engineering \& Sciences PY - 2001 VL - 2 IS - 4 SN - 1526-1506 AB - Meshless methods using least-squares approximations and kernel approximations are based on non-shifted and shifted polynomial basis, respectively. We show that, mathematically, the shifted and non-shifted polynomial basis give rise to identical interpolation functions when the nodal volumes are set to unity in kernel approximations. This result indicates that mathematically the least-squares and kernel approximations are equivalent. However, for large point distributions or for higher-order polynomial basis the numerical errors with a non-shifted approach grow quickly compared to a shifted approach, resulting in violation of consistency conditions. Hence, a shifted polynomial basis is better suited from a numerical implementation point of view. Finally, we introduce an improved finite cloud method which uses a shifted polynomial basis and a fixed-kernel approximation for construction of interpolation functions and a collocation technique for discretization of the governing equations. Numerical results indicate that the improved finite cloud method exhibits superior convergence characteristics compared to our original implementation [Aluru and Li (2001)] of the finite cloud method. KW - DO - 10.3970/cmes.2001.002.447