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81.
E. A. Sideri 《Journal of Optimization Theory and Applications》1981,35(1):9-21
In this paper, an algorithm for minimizing a convex functionalF(x), defined by the maximum of convex smooth functionalsF
i
(x), is described. The sequence of valuesF(x
n
) is monotonically decreasing, the algorithm is convergent, and it attains quadratic convergence near the solution.This work was supported by the National Research Council of Italy. 相似文献
82.
Sannay Mohamad 《Journal of Difference Equations and Applications》2013,19(6):559-575
A novel method called semi-discretization is employed in the formulation of discrete-time analogues of nonlinear delayed differential equations modelling cellular neural networks. The dynamical characteristics of the discrete-time analogues are studied. When the network parameters satisfy certain sufficient conditions which are independent of the delays, the discrete-time analogues for any choice on the discretization step-size are shown to be globally exponentially stable. The sufficient conditions are obtained by employing an appropriate form of Lyapunov sequences and these conditions correspond to those which have been obtained in the literature for the global exponential stability of continuous-time delayed cellular neural networks. Several examples and computer simulations are given to support our results and to demonstrate some of the advantages of the discrete-time analogues in numerically simulating their continuous-time counterparts. 相似文献
83.
冯克勤 《高校应用数学学报(A辑)》1992,(3)
In this paper we present a series of binary sequences which is a generalization of GMW sequences constructed by Scholtz and Welch. Our sequences have optimal autocorrelation values as m -sequences, and nice pseudo-random property. The number of such sequences is counted and the linear span of such sequences is evaluated. 相似文献
84.
85.
近年来,伽罗瓦环上的序列理论成为人们研究的热点问题.有限域上的No序列是一类伪随机序列,它在序列密码中占具十分重要的角色.本文利用伽罗瓦环上的置换,构造了伽罗瓦环Z_(p~e)上的一类新的No序列,并且研究了其线性复杂度.研究的结果表明此类No序列具有相当大的线性复杂度. 相似文献
86.
LetX be a closed subset of a topological spaceF; leta(·) be a continuous map fromX intoX; let {x
i} be a sequence generated iteratively bya(·) fromx
0 inX, i.e.,x
i+1 =a(x
i),i=0, 1, 2, ...; and letQ(x
0) be the cluster point set of {x
i}. In this paper, we prove that, if there exists a pointz inQ(x
0) such that (i)z is isolated with respect toQ(x
0), (ii)z is a periodic point ofa(·) of periodp, and (iii)z possesses a sequentially compact neighborhood, then (iv)Q(x
0) containsp points, (v) the sequence {x
i} is contained in a sequentially compact set, and (vi) every point inQ(x
0) possesses properties (i) and (ii). The application of the preceding results to the caseF=E
n leads to the following: (vii) ifQ(x
0) contains one and only one point, then {x
i} converges; (viii) ifQ(x
0) contains a finite number of points, then {x
i} is bounded; and (ix) ifQ(x
0) containsp points, then every point inQ(x
0) is a periodic point ofa(·) of periodp. 相似文献
87.
Kana Nishimori Makoto Ouchi Mitsuo Sawamoto 《Macromolecular rapid communications》2016,37(17):1414-1420
A special initiator for metal‐catalyzed living radical polymerization facilitates sequence analyses by matrix‐assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF‐MS) of alternating copolymers from styrene and maleimide derivatives. The initiator is a malonate‐based alkyl halide (DEMM‐Br), in which two ester groups are attached on the carbon neighboring to bromide, and poor electron density of the radical species allows determination of next unit to the initiator in resultant alternating copolymers due to the selective initiation to styrene derivative. Thanks to the well‐defined α‐end group, sequence of the oligomeric products via radical copolymerization of PMS and EMI with DEMM‐Br can be more simply analyzed by MALDI‐TOF‐MS, and indeed the following are clarified: the crossover propagation is almost perfectly controlled regardless of the injection ratio; a minor error event of the disordered alternating sequence containing St–St sequential unit could take place; the minor error can be suppressed with an excess amount of maleimide.
88.
It is shown that the multiplier norm of a shifted Jacobi multiplier sequence can be estimated by the (same) multiplier norm
of the original sequence uniformly with respect to the shift. Muckenhoupt’s transplantation theorem for Jacobi series is used
essentially, for which also a functional analytic understanding is given in terms of the minimality of the Jacobi system in
weighted L
p
-spaces.
相似文献
89.
Ozer TALO Feyzi BASAR 《数学学报(英文版)》2008,24(7):1205-1212
Recently, the space bvp of real or complex numbers consisting of all sequences whose differences are in the space lp has been studied by Basar, Altay [Ukrainian Math. J. 55(1)(2003), 136-147], where 1 ≤ p ≤ ∞. The main purpose of the present paper is to introduce the space bvp(F) of sequences of p-bounded variation of fuzzy numbers. Moreover, it is proved that the space bvp(F) includes the space lp(F) and also shown that the spaces bvp(F) and lp(F) axe isomorphic for 1 ≤ p ≤∞. Furthermore, some inclusion relations have been given. 相似文献
90.
Most of the literature on coded excitation describes the signal-to-noise ratio gain of a coded waveform in terms of the time-bandwidth product. We have shown that in the context of ultrasound imaging, the expression for the SNR gain provided by matched filtering a coded waveform, can be reduced to the total number of chips in the transmit signal. Hence, the SNR gain is independent of both the bandwidth and the duration of a single-chip. This concept is described in detail, clarifying this seeming contradiction. The impact of bandwidth and pulse duration on the SNR, SNR gain and axial resolution is described. Bandwidth requirements and the impact of regulatory peak-power limitations are also addressed. 相似文献