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41.
关于两两NQD列的若干极限性质 总被引:32,自引:0,他引:32
本文讨论了两两NQD列的Marcinkiewicz型弱大数律及Jamison型加权和的强稳定性,指出了两两NQD列与独立列的一个本质性区别,从而提出了解决两两NQD旬几乎处处收敛和完全收敛的一种方式。 相似文献
42.
43.
The partial order on monomials that corresponds to domination when evaluated at positive Newton sequences is fully understood. Here we take up the corresponding partial order on linear combinations of monomials. In part using analysis based upon the cone structure of the exponents in p-Newton sequences, an array of conditions is given for this new partial order. It appears that a characterization in general will be difficult. Within the case in which all coefficients are 1, the situation in which, for general sequence length, there are two monomials, each of length two and nonnegative integer exponents, the partial order is fully characterized. The characterization is combinatorial, in terms of indices in the monomials, and, already here there is much more than term-wise domination. 相似文献
44.
We consider β-expansions of formal Laurent series over finite fields. If the base β is a Pisot or Salem series, we prove that the β-expansion of a Laurent series α is automatic if and only if α is algebraic. 相似文献
45.
P. Maroni 《Journal of Difference Equations and Applications》2013,19(9):1519-1530
In the present work, we deal with the quadratic decomposition of symmetric semi-classical polynomial sequences of even class. An example from class 2 is settled. We give an integral representation of the considered symmetric form. 相似文献
46.
47.
48.
Jinhua Wang Dr. Barbara Wicher Dr. Victor Maurizot Prof. Ivan Huc 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):1031-1038
Quinoline based aromatic amide foldamers are known to adopt stable folded conformations. We have developed a synthetic approach to produce similar oligomers where all amide bonds, or part of them, have been replaced by an isosteric vinylene group. The results of solution and solid state structural studies show that oligomers exclusively containing vinylene linkages are not well folded, and adopt predominantly flat conformations. In contrast, a vinylene segment flanked by helical oligoamides also folds in a helix, albeit with a slightly lower curvature. The presence of vinylene functions also result in an extension of π-conjugation across the oligomer that may change charge transport properties. Altogether, these results pave the way to foldamers in which both structural control and specific electronic properties may be engineered. 相似文献
49.
This paper presents the theoretical analysis of adaptive multiuser RAKE receiver scheme in frequency selective fading channel for direct-sequence code division multiple access (DS-CDMA) system. Least mean square (LMS) algorithm is used to estimate the channel coefficients. Chaotic sequences are used as spreading sequence and corresponding bit error rate (BER) in closed form is derived for imperfect channel estimation conditions. Performances of chaotic sequences are compared with pseudorandom noise (PN) sequences. Under perfect synchronization assumption, various simulation results are shown to investigate the performance of the proposed system. 相似文献
50.
Pavle Mladenovic´ 《Extremes》1999,2(4):405-419
Let X
n1
*
, ... X
nn
*
be a sequence of n independent random variables which have a geometric distribution with the parameter p
n = 1/n, and M
n
*
= \max\{X
n1
*
, ... X
nn
*
}. Let Z
1, Z2, Z3, ... be a sequence of independent random variables with the uniform distribution over the set N
n = {1, 2, ... n}. For each j N
n let us denote X
nj = min{k : Zk = j}, M
n = max{Xn1, ... Xnn}, and let S
n be the 2nd largest among X
n1, Xn2, ... Xnn. Using the methodology of verifying D(un) and D'(un) mixing conditions we prove herein that the maximum M
n has the same type I limiting distribution as the maximum M
n
*
and estimate the rate of convergence. The limiting bivariate distribution of (Sn, Mn) is also obtained. Let
n, n Nn,
,
and T
n = min{M(An), M(Bn)}. We determine herein the limiting distribution of random variable T
n in the case
n ,
n/n > 0, as n . 相似文献