Zobrazeno 1 - 10
of 33
pro vyhledávání: '"Kamen G. Ivanov"'
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Constructive Approximation. 57:631-661
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Studia Mathematica. 259:339-360
Autor:
Pencho Petrushev, Kamen G. Ivanov
Publikováno v:
Geophysical Journal International. 224:181-190
SUMMARY An algorithm and software are developed for fast and accurate evaluation of the elements of the geomagnetic field represented in high-degree (>720) solid spherical harmonics at many scattered points in the space above the surface of the Earth
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Transactions of the American Mathematical Society. 373:3117-3176
A basic building block in Classical Potential Theory is the fundamental solution of the Laplace equation in ${\mathbb R}^d$ (Newtonian kernel). The main goal of this article is to study the rates of nonlinear $n$-term approximation of harmonic functi
Publikováno v:
Journal of Geodesy. 92:779-796
Gravimetric quantities are commonly represented in terms of high degree surface or solid spherical harmonics. After EGM2008, such expansions routinely extend to spherical harmonic degree 2190, which makes the computation of gravimetric quantities at
Autor:
Pencho Petrushev, Kamen G. Ivanov
Publikováno v:
Journal of Fourier Analysis and Applications. 23:1062-1096
Harmonic Besov and Triebel–Lizorkin spaces on the unit ball in \({\mathbb R}^d\) with full range of parameters are introduced and studied. It is shown that these spaces can be identified with respective Besov and Triebel–Lizorkin spaces of distri
Autor:
Pencho Petrushev, Kamen G. Ivanov
Publikováno v:
Journal of Approximation Theory. 254:105406
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Numerical Algorithms. 71:585-611
An algorithm for fast and accurate evaluation of band-limited functions at many scattered points on the unit 2-d sphere is developed. The algorithm is based on trigonometric representation of spherical harmonics in spherical coordinates and highly lo
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Applied and Computational Harmonic Analysis. 37:545-562
An iterative algorithm for stable and accurate reconstruction of band-limited functions from irregular samples on the unit 2-d sphere is developed. Geometric rate of convergence in the uniform norm is achieved. It is shown that a MATLAB realization o
Autor:
Kamen G. Ivanov, Pencho Petrushev
Publikováno v:
Advances in Computational Mathematics. 41:191-230
A method for fast evaluation of band-limited functions (spherical polynomials) at many scattered points on the unit 2-d sphere is presented. The method relies on the superb localization of the father needlet kernels and their compatibility with spher