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111.
Let (R, m) be a Cohen-Macaulay local ring of dimension d, I an mprimary ideal and K an ideal containing I. Assuming that I has minimal (almost minimal) mixed multiplicity with respect to K, we get some results on the Hilbert coefficients of fiber cones. 相似文献
112.
讨论二阶四点微分方程组边值问题u″+p(t)f(t,u(t),v(t))=0,0 t 1,v″+q(t)g(t,u(t),v(t))=0,0 t 1,u(0)=a1x(ξ1),u(1)=b1x(η1)v(0)=a2x(ξ2),v(1)=b2x(η2)如果函数f,g:[0,1]×[0,∞)×[0,∞)→[0,∞)是连续的,并赋予f、g一定的增长条件,利用Leggett-Williama不动点定理,证明了上述边值问题至少存在三对正解. 相似文献
113.
In this paper, we study the problem of existence of zero points for set-valued operators in Banach spaces. We present a simple
condition which can be used to verify that under some conditions, set-valued operators have zero points. Furthermore, we derive
the surjectivity result and the Kakutani fixed point theorem by using this condition.
相似文献
114.
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116.
Generalized quasiconvexities,cone saddle points,and minimax theorem for vector-valued functions 总被引:5,自引:0,他引:5
T. Tanaka 《Journal of Optimization Theory and Applications》1994,81(2):355-377
We establish the following theorems: (i) an existence theorem for weak type generalized saddle points; (ii) an existence theorem for strong type generalized saddle points; (iii) a generalized minimax theorem for a vector-valued function. These theorems are generalizations and extensions of the author's recent results. For such extensions, we propose new concepts of convexity and continuity of vector-valued functions, which are weaker than ordinary ones. Some of the proofs are based on a few key observations and also on the Browder coincidence theorem or the Tychonoff fixed-point theorem. Also, the minimax theorem follows from the existence theorem for weak type generalized saddle points. The main spaces with mathematical structures considered are real locally convex spaces and real ordered topological vector spaces.This paper is dedicated to Professor Kensuke Tanaka on his sixtieth birthday.This paper was written when the author was a visitor at the Department of Mathematical Science, Graduate School of Science and Technology, Niigata University, Niigata, Japan. The author is indebted to Prof. K. Tanaka for suggesting this work.The author is very grateful to Prof. P. L. Yu for his useful encouragement and suggestions and to the referees for their valuable suggestions and comments. 相似文献
117.
Banach空间中的相补问题 总被引:6,自引:0,他引:6
本文在Banach空间中研究了三类相补问题解的存在性。所得结果是[4,5,6,9,11-14]中相应结果的深入和发展。 相似文献
118.
In this paper, with the help of the Jordan-algebraic technique we introduce two new complementarity functions (C-functions)
for symmetric cone complementary problems, and show that they are continuously differentiable and strongly semismooth everywhere.
The work was partly supported by the National Natural Science Foundation of China (10671010, 70471002). 相似文献
119.
一个半正Sturm-Liouville边值问题的n个解的存在性 总被引:5,自引:0,他引:5
通过构造与非线性项有关的辅助函数并考察这个辅助函数在有界集上的性质,对于Sturm-Liouville边值问题建立了几个解的存在性,其中非线性项是下有界的.同时,给出了正解和非平凡解的一个判别方法.主要工具是锥压缩与锥拉伸型的Krasnosel’skii不动点定理. 相似文献
120.
A. V. Arutyunov 《Computational Mathematics and Mathematical Physics》2006,46(2):195-205
The equation F(x, σ) = 0,x ∈ K, in which σ is a parameter and x is an unknown taking values in a given convex cone in a Banach space X, is considered. This equation is examined in a neighborhood of a given solution (x *, σ*) for which the Robinson regularity condition may be violated. Under the assumption that the 2-regularity condition (defined in the paper), which is much weaker than the Robinson regularity condition, is satisfied, an implicit function theorem is obtained for this equation. This result is a generalization of the known implicit function theorems even for the case when the cone K coincides with the entire space X. 相似文献