Results 131 to 140 of about 21,571 (171)

Strong summability of Riesz means

Mathematical Notes of the Academy of Sciences of the USSR, 1986
Let \(\{u_ n(x)\}\) be a complete orthonormalized system of eigenfunctions of the self-adjoint extension of Laplace operator - \(\Delta\) in N-dimensional domain \(\Omega\) with discrete spectrum, and let \(\lambda_ n=\mu_ n^ 2\) be the corresponding eigenvalues numbered in increasing order.
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Lectures on Bochner-Riesz Means

1987
This book is concerned with the modern theory of Fourier series. Treating developments since Zygmund's classic study, the authors begin with a thorough discussion of the classical one-dimensional theory from a modern perspective. The text then takes up the developments of the 1970s, beginning with Fefferman's famous disc counterexample. The culminating
Katherine Michelle Davis, Yang-Chun Chang   +1 more
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Inclusion Relations for General Riesz Typical Means

Canadian Mathematical Bulletin, 1974
Let α be a non-negative real number, λ≡{λ,n}(n≥0) a strictly increasing unbounded sequence with λ0≥0 and let be an arbitrary series with partial sums s≡{sn}. Writewhere s(t)=sn for λn<t≤λn+1, s(t)=0 for 0≤t≤λ0. The series ∑ an or the sequence of partial sums s={sn} is summable to ṡ by the Riesz method (R, λ, α) ifas ω→∞.
Jakimovski, A., Tzimbalario, J.
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A note on Riesz means

Mathematical Proceedings of the Cambridge Philosophical Society, 1968
1. For the familiar definition of (R, λn, κ), (R*, λn, κ) and (N, p) means and their notations, see, for example (3). If {fn} is any arbitrary sequence, we adopt the convention throughout that f−1 = 0. A method of absolute summability |A| is said to be ineffective if it is absolutely regular and sums only absolutely convergent sequences.
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On Abel—Poisson type and Riesz means

Analysis Mathematica, 1981
В работе исследуются ядра методов суммиро вания типа Абеля—Пуассона и Рис са, применяемых к кратны м интегралам Фурье. Вы ясняются условия на параметры, определяющие эти методы, при которы х их ядра неотрицател ьны. Полученные результа ты можно сформулировать в тер минах положительной определенности неко торых функций.
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Inclusion relations for Riesz typical means

Mathematical Proceedings of the Cambridge Philosophical Society, 1972
AbstractNecessary and sufficient conditions for sequence-to-sequence or sequence-to-function summability method to include (R, λ, α), when 1 < α ≤ 2, are given. Also, for suitably restricted sequences λ, necessary and sufficient conditions for a series-to-sequence or series-to-function summability method to include (R, λ, α) for 1 < α ≤ 2 are ...
Jakimovski, A., Tzimbalario, J.
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Riesz Means on Compact Riemannian Symmetric Spaces

Mathematische Nachrichten, 1994
AbstractWe study approximation properties of the Riesz means on compact symmetric spaces of rank one. To do so we establish equivalences between the Riesz means and Peetre K‐moduli and estimate the weak type and the uniform approximation of the Riesz means at the critical index.
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The Riesz Mean Ergodic Theorem

2019
If T is a non-expansive linear map of a uniformly convex Banach space, then all the fixed points of T are recovered by means of a limit procedure.
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A note on the “hyperbolic” Bochner-Riesz means

Proceedings of the American Mathematical Society, 1984
We consider the L p ( R 2 ) {L^p}({{\mathbf {R}}^2}) boundedness properties of the Fourier multiplier m ( ξ
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On Fejer and Bochner-Riesz Means

Journal of Fourier Analysis and Applications, 2005
For the Fejer means on \(L_p(R), 1\le p\le\infty\) an equivalence between the rate of its convergence and an appropriate K-functional is established. For the Bochner-Riesz means on \(L_p(R^d), 1\le p\le\infty, d=1,2,\dots\) an equivalence between the rate of convergence and the corresponding K-functional is obtained.
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