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121.
122.
Sergei V. Astashkin Lech Maligranda 《Proceedings of the American Mathematical Society》2004,132(10):2929-2938
We show that if is a rearrangement invariant space on that is an interpolation space between and and for which we have only a one-sided estimate of the Boyd index 1/p, 1 < p < \infty$">, then is an interpolation space between and . This gives a positive answer for a question posed by Semenov. We also present the one-sided interpolation theorem about operators of strong type and weak type .
123.
In this paper we consider a problem of distance selection in the arrangement of hyperplanes induced by n given points. Given a set of n points in d-dimensional space and a number k,
, determine the hyperplane that is spanned by d points and at distance ranked by k from the origin. For the planar case we present an O(nlog2n) runtime algorithm using parametric search partly different from the usual approach [N. Megiddo, J. ACM 30 (1983) 852]. We establish a connection between this problem in 3-d and the well-known 3SUM problem using an auxiliary problem of counting the number of vertices in the arrangement of n planes that lie between two sheets of a hyperboloid. We show that the 3-d problem is almost 3SUM-hard and solve it by an O(n2log2n) runtime algorithm. We generalize these results to the d-dimensional (d4) space and consider also a problem of enumerating distances. 相似文献
124.
The spectrum of xenon excited in a low-inductance vacuum spark was photographed at high resolution in the region of 9.5-15.5 nm. The observed transitions were identified as belonging to ions from Xe8+ to Xe13+. In the region of importance for extreme-ultraviolet lithography around 13.4 nm, the strongest lines were identified as 4d8-4d7 5p transitions in Xe10+. The identifications were made by use of energy parameters extrapolated along the isoelectronic sequence. 相似文献
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Khoroshun DV Inagaki A Suzuki H Vyboishchikov SF Musaev DG Morokuma K 《Journal of the American Chemical Society》2003,125(33):9910-9911
The reaction of a trinuclear polyhydride complex Ru3H5(C5H5)3 with cyclopentadiene, C5H6, has been studied computationally. A mechanism for the experimentally observed selective C-C bond activation is proposed. All three Ru centers participate in various steps of the mechanism. The catalytic involvement of two cluster hydrides in the transformation of the C5Hn fragment is emphasized. 相似文献
128.
We investigate Fuglede's spectral set conjecture in the special case when the set in question is a union of finitely many unit intervals in dimension 1. In this case, the conjecture can be reformulated as a statement about multiplicative properties of roots of associated with the set polynomials with (0,1) coefficients. Let be an N-term polynomial. We say that {θ1,θ2,…,θN−1} is an N-spectrum for A(x) if the θj are all distinct and
129.
Helmut?HarbrechtEmail author Sergei?Pereverzev Reinhold?Schneider 《Numerische Mathematik》2003,95(1):123-143
It is well known, that pseudodifferential equations of negative order considered in Sobolev spaces with small smoothness indices are ill–posed. On the other hand, it is known that efficient discretization schemes with properly chosen discretization parameters allow to obtain a regularization effect for such equations. The main accomplishment of the present paper is the principle for the adaptive choice of the discretization parameters directly from noisy discrete data. We argue that the combination of this principle with wavelet–based matrix compression techniques leads to algorithms which are order–optimal in the sense of complexity. 相似文献
130.
Sergei V. Zubov 《Southeast Asian Bulletin of Mathematics》2000,24(1):155-172
Consider a new concept of stability of the so-called rated motion of a system of an ordinary differential equations. A rated motion need not be a solution of this system at all. In terms of Lyapunovs direct method, formulate and prove certain statements about rated stability, asymptotically rated stability, and rated unstability of zero motion of a system of an ordinary differential equations.AMS Subject Classification (1991): 34D05 34D35 93D30 93D20 相似文献