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1.
本文把「3」的主要结果从Hilbert空间推广到一致凸的Banach空间,证明了一致凸的Banach空间上的渐近非扩张映象的迭代序列的收敛性。  相似文献   

2.
张果平 《数学杂志》1998,18(2):216-220
本文的目标是利用凸性指标给出Banach空间具有Banach-Sake性质的一个充分条件,从而推广Kankutani定理。  相似文献   

3.
关于度量投影的连续性   总被引:10,自引:1,他引:9  
王建华 《应用数学》1995,8(1):80-84
本文引入的Banach空间的(C-I)、(C-Ⅱ),(C-Ⅲ)等几何性质,证明了如下结果。设M是Banach空间的逼近凸子集,如果Banach空间有性质(C-I),(C-Ⅱ)(C-Ⅲ),则度量投影PM连续(范数-范数上半连续,范数-弱上半连续)。这些结果推广了文(4,7,8)相应的定理。最近,D.Kutzarova,Bor-Luh Lin等引入了一些新的凸性空间,本文还研究了这些凸性空间中度量投影  相似文献   

4.
Banach空间中强增生算子的非线性方程的解的迭代构造   总被引:4,自引:0,他引:4  
本文研究p一致光滑Banach空间X中Ishikawa迭代法.受Deng与Tan,Xu的启发,证明了,当T是从X到自身的Lipschitz强增生算子时,Ishikawa迭代法强收敛到方程Tx=f的唯一解;当T是从X的有界闭凸子集到自身的Lipschitz严格伪压缩映象时,Ishikawa迭代法强收敛到T的唯一不动点.通过去掉限制limn→∞β=0或limn→∞α=limn→∞β=0,结果改进与推广了Tan,Xu的定理4.1与定理4.2,也把Deng的定理1与定理2推广到了p一致光滑Banach空间的背景.  相似文献   

5.
南朝勋 《数学研究》1994,27(2):82-86
本文讨论强凸性、L-kR,LωR和(G)性质之间的关系,指出强凸性介于LωR和(G)性质之间,证明光滑的有(G)性质的Banach空间是强凸的,此外指出存在一个Banach空间X,它是LωR但对任意自然数k,X不是L-kR.  相似文献   

6.
Banach空间中广义正交分解定理与广义正交可补子空间   总被引:22,自引:1,他引:21  
王玉文  王辉 《数学学报》2001,44(6):1045-105
本文首先将 Hilbert空间中的Riesz正交分解定理推广到 Banach空间,得到 Banach空间广义正交分解定理.然后,利用此定理讨论由James R.C.[1]引入的Banach空间中正交概念及 Nashed M.Z.[2]引入的 Banach空间中(广义)正交可补子空间,得到判别子空间广义正交可补的充分必要条件,并由此给出Hilbert空间的一个新特征.  相似文献   

7.
甘师信 《数学杂志》1994,14(3):387-395
本文证明了Banach空间值鞅的一些不等式,讨论了Banach空间的凸性及光滑性与某些鞅不等的式的联系,给出了Hilbert空间的一个鞅不等式刻划,同时还讨论了一致P光滑空间中鞅的弱大数定律,本文的结论推广与改进了很多熟知的定理。  相似文献   

8.
本文处理能在Banach空间中实现的线性连续时间系统.这里,输入、输出和状态空间都是无穷维Banach空间.我们证明:加权模式有Banach空间实现的充要条件是它强连续且为指数阶.对状态算子是解析半群的无穷小生成元的情况,得到了Banach空间实现的存在性定理.所有定理都是在时间域中给出的.  相似文献   

9.
Banach空间中渐近正则的Lipschitz半群的不动点定理   总被引:1,自引:0,他引:1  
本文首先定义了渐近正则的Lipschitz半群的概念.其次,证明了p一致凸Banach空间中渐近正则的Lipschitz半群的不动点定理.同时也证明了具有正规结构系数的一致凸Eanach空间中的渐近正则的Lipschitz半群的一个新的不动点定理.  相似文献   

10.
本文研究了Banach空间的弱序列紧性.Banach空间X称为有(w)性质,如果X(X的共轭空间)的每个有界序列有弱收敛子列.我们证明了,如果Banach空间X有(w)性质,那么lp(X)(1≤p<+∞)与c0(X)也有(w)性质.  相似文献   

11.
This paper points out some fatal errors in the equivalent formulations used in Noor 2011 [Noor MA. Projection iterative methods for solving some systems of general nonconvex variational inequalities. Applied Analysis. 2011;90:777–786] and consequently in Noor 2009 [Noor MA. System of nonconvex variational inequalities. Journal of Advanced Research Optimization. 2009;1:1–10], Noor 2010 [Noor MA, Noor KI. New system of general nonconvex variational inequalities. Applied Mathematics E-Notes. 2010;10:76–85] and Wen 2010 [Wen DJ. Projection methods for a generalized system of nonconvex variational inequalities with different nonlinear operators. Nonlinear Analysis. 2010;73:2292–2297]. Since these equivalent formulations are the main tools to suggest iterative algorithms and to establish the convergence results, the algorithms and results in the aforementioned articles are not valid. It is shown by given some examples. To overcome with the problems in these papers, we consider a new system of extended regularized nonconvex variational inequalities, and establish the existence and uniqueness result for a solution of the aforesaid system. We suggest and analyse a new projection iterative algorithm to compute the unique solution of the system of extended regularized nonconvex variational inequalities which is also a fixed point of a nearly uniformly Lipschitzian mapping. Furthermore, the convergence analysis of the proposed iterative algorithm under some suitable conditions is studied. As a consequence, we point out that one can derive the correct version of the algorithms and results presented in the above mentioned papers.  相似文献   

12.
非凸半定规划的广义Fakars引理及最优性条件   总被引:1,自引:0,他引:1  
1引言在本文中,我们用(?),S~n,S_ ~n分别表示有限维向量空间,n阶对称矩阵空间及n阶半正定矩阵锥.我们考虑如下形式的非凸半定规划问题:  相似文献   

13.
Let X be a space of homogeneous type with finite measure. Let T be a singular integral operator which is bounded on Lp (X), 1 < p <∞. We give a sufficient condition on the kernel k(x,y) of Tso that when a function b ∈ BMO (X) ,the commutator [b, T] (f) = T (b f) - bT (f) is aounded on spaces Lp for all p, 1 < p <∞.  相似文献   

14.
In this paper, we take a little modification to the Wei–Yao–Liu nonlinear conjugate gradient method proposed by Wei et al. [Z. Wei, S. Yao, L. Liu, The convergence properties of some new conjugate gradient methods, Appl. Math. Comput. 183 (2006) 1341–1350] such that the modified method possesses better convergence properties. In fact, we prove that the modified method satisfies sufficient descent condition with greater parameter in the strong Wolfe line search and converges globally for nonconvex minimization. We also extend these results to the Hestenes–Stiefel method and prove that the modified HS method is globally convergent for nonconvex functions with the standard Wolfe conditions. Numerical results are reported by using some test problems in the CUTE library.  相似文献   

15.
《Optimization》2012,61(11):1331-1345
Li and Sun [D. Li and X.L. Sun, Existence of a saddle point in nonconvex constrained optimization, J. Global Optim. 21 (2001), pp. 39--50; D. Li and X.L. Sun, Convexification and existence of saddle point in a p-th-power reformulation for nonconvex constrained optimization, Nonlinear Anal. 47 (2001), pp. 5611--5622], present the existence of a global saddle point of the p-th power Lagrangian functions for constrained nonconvex optimization, under second-order sufficiency conditions and additional conditions that the feasible set is compact and the global solution of the primal problem is unique. In this article, it is shown that the same results can be obtained under additional assumptions that do not require the compactness of the feasible set and the uniqueness of global solution of the primal problem.  相似文献   

16.
In this paper, new necessary conditions for Pareto minimal points to sets and Pareto minimizers for constrained multiobjective optimization problems are established without the sequentially normal compactness property and the asymptotical compactness condition imposed on closed and convex ordering cones in Bao and Mordukhovich [10] and Durea and Dutta [5], respectively. Our approach is based on a version of the separation theorem for nonconvex sets and the subdifferentials of vector-valued and set-valued mappings. Furthermore, applications in mathematical finance and approximation theory are discussed.  相似文献   

17.
張素誠 《数学学报》1954,4(3):365-379
<正> §1.設X是一個拓撲空間,其中任何二點可以用弧聯結。以x_o∈X為參考點,那麼可以定義π_r(X,x_o)(r=1,2,…)。這種羣的元素全體,成為一個集E。在E中有魏德海乘積[2],即α,β為E中一點,那麼[α,β]也是E中一點。關於魏德海乘積的重覆使用問題,就文獻而諭,首先在W.S.Massey[6]  相似文献   

18.
Armijo线性搜索下Hager-Zhang共轭梯度法的全局收敛性   总被引:2,自引:0,他引:2       下载免费PDF全文
Hager和Zhang[4]提出了一种新的非线性共轭梯度法(简称 HZ 方法), 并证明了该方法在 Wolfe搜索和 Goldstein 搜索下求解强凸问题的全局收敛性.但是HZ方法在标准Armijo 搜索下求解非凸问题是否全局收敛尚不清楚.该文提出了一种保守的HZ共轭梯度法,并且证明了这种方法在 Armijo 线性搜索下求解非凸优化问题的全局收敛性.此外,作者给出了一些 数值结果以检验该方法的有效性.  相似文献   

19.
It is well known that the sufficient descent condition is very important to the global convergence of the nonlinear conjugate gradient method. In this paper, some modified conjugate gradient methods which possess this property are presented. The global convergence of these proposed methods with the weak Wolfe–Powell (WWP) line search rule is established for nonconvex function under suitable conditions. Numerical results are reported. This work is supported by Guangxi University SF grands X061041 and China NSF grands 10761001.  相似文献   

20.
Branch and bound approaches for nonconvex programming problems had been given in [1] and [4]. Crucial for both are the use of rectangular partitions, convex envelopes and separable nonconvex portions of the objective function and constraints. We want to propose a similar algorithm which solves a sequence of problems in each of which the objective function is convex or even linear. The main difference between this approach and previous approaches is the use of general compact partitions instead of rectangular ones and a different refining rule such that the algorithm does not rely on the concept of convex envelopes and handles non-separable functions.First we describe a general algorithm and prove a convergence theorem under suitable regularity assumptions. Then we give as example an algorithm for concave minimization problems.  相似文献   

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