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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
We study applications of the theory of quadratic differentials to the solution of new extremal problems of nonoverlapping
domains with free poles on rays and generalize known results to a certain class of open sets.
__________
Translated from Neliniini Kolyvannya, Vol. 10, No. 4, pp. 435–442, October–December, 2007. 相似文献
992.
We introduce some relative versions of star selection principles first considered in [5], [11]. Some of the work extends results
from [4], [5] and gives some examples.
相似文献
993.
The 57Fe Mössbauer effect study at 5.0 K and in an external magnetic field of 9.0 T on a high-quality stable decagonal quasicrystal Al65Co15Cu19.9Fe0.1 is presented. It is shown that the iron atoms are located in two distinct classes of sites. The values of the principal component of the electric field gradient tensor and the asymmetry parameter at these sites are, respectively, ?1.90(10)?×?1021 V/m2, 0.97(15) and ?3.95(12)?×?1021 V/m2, 0.00(17). 相似文献
994.
The paper addresses bivariate surface fitting problems, where data points lie on the vertices of a rectangular grid. Efficient
and stable algorithms can be found in the literature to solve such problems. If data values are missing at some grid points,
there exists a computational method for finding a least squares spline by fixing appropriate values for the missing data.
We extended this technique to arbitrary least squares problems as well as to linear least squares problems with linear equality
constraints. Numerical examples are given to show the effectiveness of the technique presented.
AMS subject classification (2000) 65D05, 65D07, 65D10, 65F05, 65F20 相似文献
995.
A. I. Maksimov 《Thermophysics and Aeromechanics》2007,14(4):469-492
The paper briefly describes the life and activities of F.A. Zander and Yu.V. Kondratyuk (A.I. Shargei), pioneers of domestic
rocket engineering who made a significant contribution to the development of cosmonautics and rocket technologies. The main
ideas and proposals of these prominent scientists and inventors in the field of rocket and space engineering, which found
their application in space conquering, are considered.
To the 120th anniversary of F.A. Zander and 110th anniversary of Yu.V. Kondratyuk 相似文献
996.
997.
Stadia are popular models of chaotic billiards introduced by Bunimovich in 1974. They are analogous to dispersing billiards
due to Sinai, but their fundamental technical characteristics are quite different. Recently many new results were obtained
for various chaotic billiards, including sharp bounds on correlations and probabilistic limit theorems, and these results
require new, more powerful technical apparatus. We present that apparatus here, in the context of stadia, and prove “regularity”
properties.
相似文献
998.
We give a new independent self-dual 3-basis for the trivial variety with two binary operations.
Received October 24, 2006; accepted in final form January 25, 2007. 相似文献
999.
A mistake concerning the ultra LI-ideal of a lattice implication algebra is pointed out, and some new sufficient and necessary conditions for an LI-ideal to be an ultra LI-ideal are given. Moreover, the notion of an LI-ideal is extended to MTL-algebras, the notions of a (prime, ultra, obstinate, Boolean) LI-ideal and an ILI-ideal of an MTL-algebra are introduced, some important examples are given, and the following notions are proved to be equivalent in MTL-algebra: (1) prime proper LI-ideal and Boolean LI-ideal, (2) prime proper LI-ideal and ILI-ideal, (3) proper obstinate LI-ideal, (4) ultra LI-ideal.
This work was supported by the Zhejiang Provincial Natural Science Foundation of China (Grant No. Y605389) and K. C. Wong
Magna Fund in Ningbo University. 相似文献
1000.
We use the Schaefer fixed-point theorem, combined with the Bressan-Colombo selection theorem for lower-semicontinuous multivalued
operators with nonempty closed and decomposable values, for the investigation of the existence of solutions for first-and
second-order impulsive functional differential inclusions with variable times.
Published in Neliniini Kolyvannya, Vol. 10, No. 4, pp. 443–463, October–December, 2007. 相似文献