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991.
简要介绍了利用高温高压合成发现的超导系列CuBa2Can-1CunO2n+2+δ,即Cu-12n(三元数法)或Cu-12(n-1)n(四元数法),简称Cu-系。比较了Cu-系和其它主要高温超导体的结构和主要性质,指出了Cu-系和YBa2Cu3O6的同构关系,以及Cu-系具有的良好的高温高场特性。Cu-系超导体因仅含碱土和铜的氧化物,化学组成简单、经济、安全,具有潜在的应用开发前景。 相似文献
992.
A 2 × 2 clocked buffered switch is a device used in data-processing networks for routing messages from one node to another.
The message handling process of this switch can be modelled as a two-server, time slotted, queueing process with state space
the number of messages (xn , yn) present at the servers at the end of a time slot. The xn , yn-process is a two-dimensional nearest-neighbour random walk. In the present study the bivariate generating function Φ(p,q)
of the stationary distribution of this random walk is determined, assuming that this distribution exists. Φ(p,q) is known,
whenever Φ(p,0) and Φ(0,q) are known. The essential points of the present study are the construction of these two functions
from the knowledge of their poles and zeros and the simple determination of these poles and zeros.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
993.
Andrew Ya. Olenko Tibor K. Pogány 《Journal of Mathematical Analysis and Applications》2006,324(1):262-280
Time shifted aliasing error upper bound extremals for the sampling reconstruction procedure are fully characterized. Sharp upper bounds are found on the aliasing error of truncated cardinal series and the corresponding extremals are described for entire functions from certain specific Lp, p>1, classes. Analogous results are obtained in multidimensional regular sampling. Truncation error analysis is provided in all cases considered. Moreover, sharpness of bounding inequalities, convergence rates and various sufficient conditions are discussed. 相似文献
994.
W.T. Sulaiman 《Journal of Mathematical Analysis and Applications》2006,322(2):1224-1230
Extension and improvement has been made on a recent result proved by Mazhar [S.M. Mazhar, Absolute summability factors of infinite series, Kyungpook Math. J. 39 (1999) 67-73] concerning absolute summability factors of infinite series. 相似文献
995.
本文给出了p—级数与广义积分∫10lnk-1x1-xdx,∫10lnk-1x1+xdx,∫10lnk-1x1-x2dx,∫10lnk-1x1+x2dx之间的关系.并通过一些p—级数的求和,给出了上述广义积分中某些积分的积分值. 相似文献
996.
设ψ(n)是Euler函数,r是正实数.以E(x,r)表示和式的渐近公式中的误差项,本文研究了E(x,r)的算术均值和积分均值. 相似文献
997.
M. Hasanov 《Journal of Mathematical Analysis and Applications》2008,342(2):766-772
Basis problems for self-adjoint matrix valued functions are studied. We suggest a new and nonstandard method to solve basis problems both in finite and infinite dimensional spaces. Although many results in this paper are given for operator functions in infinite dimensional Hilbert spaces, but to demonstrate practicability of this method and to present a full solution of basis problems, in this paper we often restrict ourselves to matrix valued functions which generate Rayleigh systems on the n-dimensional complex space Cn. The suggested method is an improvement of an approach given recently in our paper [M. Hasanov, A class of nonlinear equations in Hilbert space and its applications to completeness problems, J. Math. Anal. Appl. 328 (2007) 1487-1494], which is based on the extension of the resolvent of a self-adjoint operator function to isolated eigenvalues and the properties of quadratic forms of the extended resolvent. This approach is especially useful for nonanalytic and nonsmooth operator functions when a suitable factorization formula fails to exist. 相似文献
998.
本文讨论一阶自回归模型自回归参数$\phi$的变点问题. 对于一阶自回归模型, 在模型的白噪声序列的方差$\sigma^2$已知和未知的条件下, 利用最大似然方法, 我们分别讨论了模型自回归参数$\phi$的Abrupt Change-Point 和Gradual Change-Point的检测问题. 相似文献
999.
We study combinatorial properties of the alternating subgroup of a Coxeter group, using a presentation of it due to Bourbaki. 相似文献
1000.
In this topic, a new approach to the analysis of time-variation dynamics is proposed by use of Legendre series expansion and
Legendre integral operator matrix. The theoretical basis for effective solution of time-variation dynamics is therefore established,
which is beneficial to further research of time-variation science.
Supported by Shanghai Key Project Research Foundation. 相似文献