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991.
LIPSCHITZ ESTIMATES FOR MULTILINEAR SINGULAR INTEGRALS,Ⅱ 总被引:3,自引:0,他引:3
In this paper, the authors study two classes of multilinear singular integrals and obtain their boundedness from Lebesgue spaces to Lipschitz spaces and from Herz type spaces to central Campanato spaces. Moreover, the authors also consider the extreme cases. 相似文献
992.
On sums of a prime and four prime squares in short intervals 总被引:1,自引:0,他引:1
Xian-Meng Meng 《Acta Mathematica Hungarica》2004,105(4):261-283
993.
Banach空间中具有数列的渐近拟非扩张型映象的不动点及其具有误差的Ishikawa迭代逼近 总被引:1,自引:0,他引:1
孟京华 《高等学校计算数学学报》2008,30(3)
1引言及相关定义 引文[1~5]讨论了渐近非扩张映象和渐近非扩张型映象不动点的迭代逼近问题.文[6]改进了文[1]中条件,将T由渐近非扩张型映象推广到T是渐近拟非扩张型映象. 相似文献
994.
以2-噻吩甲醛为原料,通过与盐酸羟胺的肟化反应制得2-噻吩甲醛肟,然后将其在氢氧化钠水溶液中用锌粉还原生成了2-噻吩甲胺。提供了一条合成2-噻吩甲胺的新路线,2步反应的总收率为64%。文中对上述2步反应的条件分别进行了优化。考察了溶液酸碱度,温度和时间对肟化反应的影响,并 相似文献
995.
Let be a set of at least two vertices in a graph . A subtree of is a -Steiner tree if . Two -Steiner trees and are edge-disjoint (resp. internally vertex-disjoint) if (resp. and ). Let (resp. ) be the maximum number of edge-disjoint (resp. internally vertex-disjoint) -Steiner trees in , and let (resp. ) be the minimum (resp. ) for ranges over all -subset of . Kriesell conjectured that if for any , then . He proved that the conjecture holds for . In this paper, we give a short proof of Kriesell’s Conjecture for , and also show that (resp. ) if (resp. ) in , where . Moreover, we also study the relation between and , where is the line graph of . 相似文献
996.
Virasoro constraint is the operator algebra version of one-loop equation for a Hermitian one-matrix model, and it plays an important role in solving the model. We construct the realization of the Virasoro constraint from the Conformal Field Theory (CFT) method. From multi-loop equations of the one-matrix model, we get a more general constraint. It can be expressed in terms of the operator algebras, which is the Virasoro subalgebra with extra parameters. In this sense, we named as generalized Virasoro constraint. We enlarge this algebra with central extension, this is a new kind of algebra, and the usual Virasoro algebra is its subalgebra. And we give a bosonic realization of its subalgebra. 相似文献
997.
In this study, we focus on the solutions of the Li\''enard equation being bounded in the future and characterize the almost automorphic, asymptotically almost automorphic, and weighted pseudo almost automorphic dynamics. An example is presented to illustrate the main findings. 相似文献
998.
Explicit exact periodic wave solutions and their limit forms for a long waves-short waves model 下载免费PDF全文
A long waves-short waves model is studied by using the approach of dynamical systems. The sufficient conditions to guarantee the existence of solitary wave, kink and anti-kink waves, and periodic wave in different regions of the parametric space are given. All possible explicit exact parametric representations of above traveling waves are presented. When the energy of Hamiltonian system corresponding to this model varies, we also show the convergence of the periodic wave solutions, such as the periodic wave solutions converge to the solitary wave solutions,
kink and anti-kink wave solutions, and periodic wave solutions, respectively. 相似文献
999.
Rui Shen Zhiqing Meng Chuangyin Dang Min Jiang 《Numerical Functional Analysis & Optimization》2017,38(11):1473-1489
In this paper, an algorithm of barrier objective penalty function for inequality constrained optimization is studied and a conception–the stability of barrier objective penalty function is presented. It is proved that an approximate optimal solution may be obtained by solving a barrier objective penalty function for inequality constrained optimization problem when the barrier objective penalty function is stable. Under some conditions, the stability of barrier objective penalty function is proved for convex programming. Specially, the logarithmic barrier function of convex programming is stable. Based on the barrier objective penalty function, an algorithm is developed for finding an approximate optimal solution to an inequality constrained optimization problem and its convergence is also proved under some conditions. Finally, numerical experiments show that the barrier objective penalty function algorithm has better convergence than the classical barrier function algorithm. 相似文献
1000.