Approximation by multivariate quasi-projection operators and Fourier multipliers

نویسندگان

چکیده

Multivariate quasi-projection operators Qj(f,φ,φ˜), associated with a function φ and distribution/function φ˜, are considered. The is supposed to satisfy the Strang-Fix conditions compatibility condition φ˜. Using technique based on Fourier multipliers, we study approximation properties of such for functions f from anisotropic Besov spaces Lp 1≤p≤∞. In particular, upper lower estimates Lp-error in terms moduli smoothness best approximations obtained.

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ژورنال

عنوان ژورنال: Applied Mathematics and Computation

سال: 2021

ISSN: ['1873-5649', '0096-3003']

DOI: https://doi.org/10.1016/j.amc.2021.125955