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1.
引入有限维向量空间的γ-锥和严格γ-锥的概念.证明了γ-锥是一类闭锥,严格γ-锥是一类开锥.并且,研究了γ-锥和严格γ-锥与较多锥、严格较多锥及它们的闭包和内部之间的关系.  相似文献   

2.
r-锥和严格r-锥   总被引:2,自引:0,他引:2  
引入有限维向量空间的r-锥和严格r-锥的概念,证明了r-锥是一类闭锥,严格r-锥是一类开锥。并且,研究了r-锥和严格r-锥与较多锥、严格较多锥及它们的闭包和内部之间的关系。  相似文献   

3.
许以超 《中国科学A辑》1981,24(4):385-395
本文给出方型锥的共轭锥上第一类齐性siegel域的完全分类.给出方型锥及共轭方型锥上第一类齐性siegel域的方阵表示.在文献[1]中,我们给出了方型锥上第一类齐性siegel域的完全分类.N-齐性锥VN称为方型锥,如果本文考虑共轭方型锥.N-齐性锥VN称为共轭方型锥,如果我们给出了其上第一类齐性siegel域的完全分类.并且证明了方型锥的共轭锥必线性等价于共轭方型锥.最后,我们列出了方型锥及共轭方型锥在线性等价下的标准锥的方阵表达形式.证明了方型锥及共轭方型锥线性等价当且仅当这些锥线性等价于自共轭锥.本文所用的符号和文献[1-3]相同.  相似文献   

4.
锥拟凸集值映射与集值映射的锥半连续性   总被引:1,自引:0,他引:1  
本文借助锥界集定义了一种新的锥拟凸集值映射,并且利用广义Minkowski泛函讨论了锥半连续及锥外上半连续集值映射的锥拟凸性.  相似文献   

5.
约束锥扰动多目标规划锥有效解集的闭性和半连续性   总被引:4,自引:0,他引:4  
本文研究拓扑向量空间中目标映射和约束映射均为连续,约束映射的约束锥为半连续的条件下,受扰动可达目标集的锥有效点集和锥弱有效点集的闭性、半连续性和锥半连续性.在此基础上,得到了约束锥扰动多目标规划问题的锥有效解集和锥弱有效解集的闭性和半连续性.  相似文献   

6.
宋军  龚循华 《运筹学学报》2007,11(2):51-58,106
本文引进了一种新的锥的扩张方式,并对新的扩张锥和原来的锥的关系作了讨论,借助这种新的概念,在无限维空间中给出了向量优化问题的锥有效解的近似方法.  相似文献   

7.
本文在自反Banach空间中引进了锥弱连续映射和点集的弱连通概念.在讨论锥弱连续和锥拟凸映射以及锥最小上界的几个性质的基础上,证明了当象集为锥凸集时定义在自反Ba- nach空间中的有界闭凸集上的锥弱连续和锥拟凸映射多目标最优化问题的锥有效解集是弱连通的.  相似文献   

8.
周德堂 《数学季刊》1991,6(1):105-106
M.A.Kransnosel'skii在《Positive solutions of operator equations》一书中引入了正则锥和弱正则锥的概念,显然正则锥一定是弱正则锥。本文证明了弱正则锥并不比正则锥广泛,即:在一切Banach空间中弱正则锥是正则的,从而为非赋范线性拓扑空间中引入正则性提供了思路。  相似文献   

9.
本文指出了文献 [1 ]在张量空间中定义的两种锥是一致的 ,证明了它们是张量空间中的最小真正锥 ,并可用来表示有限维实空间中由锥不变算子所组成的锥 ,因而可用来研究锥不变算子 .  相似文献   

10.
锥连续锥拟凹向量函数最大化问题有效解集的连通性   总被引:1,自引:0,他引:1  
本文讨论了锥连续函数及锥最大下果的性质,在此基础上讨论了锥连续锥拟凹向量函数最大化问题有效解集的连通性,证明了当象集为锥凸集时锥有效解集是连通的。  相似文献   

11.
In this paper, the author first introduces the concept of generalized algebraic cone metric spaces and some elementary results concerning generalized algebraic cone metric spaces. Next, by using these results, some new fixed point theorems on generalized (complete) algebraic cone metric spaces are proved and an example is given. As a consequence, the main results generalize the corresponding results in complete algebraic cone metric spaces and generalized complete metric spaces.  相似文献   

12.
在偏锥度量空间的基础上,介绍了偏锥b-度量空间的相关概念,提出了偏锥b-度量空间和锥b-度量空间的关系,并给出了一个简单的例子,最后研究了偏锥b-度量空间中在没有正规性的条件下的一些不动点定理,从而推广了巴拿赫压缩原理.  相似文献   

13.
Copositive optimization problems are particular conic programs: optimize linear forms over the copositive cone subject to linear constraints. Every quadratic program with linear constraints can be formulated as a copositive program, even if some of the variables are binary. So this is an NP-hard problem class. While most methods try to approximate the copositive cone from within, we propose a method which approximates this cone from outside. This is achieved by passing to the dual problem, where the feasible set is an affine subspace intersected with the cone of completely positive matrices, and this cone is approximated from within. We consider feasible descent directions in the completely positive cone, and regularized strictly convex subproblems. In essence, we replace the intractable completely positive cone with a nonnegative cone, at the cost of a series of nonconvex quadratic subproblems. Proper adjustment of the regularization parameter results in short steps for the nonconvex quadratic programs. This suggests to approximate their solution by standard linearization techniques. Preliminary numerical results on three different classes of test problems are quite promising.  相似文献   

14.
15.
锥拟凸集值映射多目标优化的解集的连通性   总被引:1,自引:0,他引:1  
凌晨 《运筹学学报》2001,5(2):33-40
在一般拓扑向量空间中,本文引进了一类锥进凸(锥严格拟凸)集值映射。并在目标映射是锥拟凸(锥严格拟凸)和上半连续的条件下,利用Minkowski泛函,证明了弱有效解(有效解)集是连通的。文[9]中的结论是本文所得结果大目标映射为单值和拓扑空间为格的情况下的特例。  相似文献   

16.
Models of six different cyclone separator designs have been investigated numerically to study the effect of changing cone length on the gas flow field. The cone length was changed in two ways, one by fixing the cone diameter and the other by fixing the cone angle. The Reynolds stress model was applied to predict the turbulence of gas flow. The model was validated by comparing the numerical results to published experimental data. The results show that, for the cyclone without cylindrical part, the pressure drop and the value of tangential and axial velocity components increase with increasing cone length with fixed cone angle until they reach maximum value. It was found that increasing the cone length with the same cone diameter increases the back flow and the lip leakage below the vortex finder. The back flow and the lip leakage phenomena was observed to be reduced by increasing cone length with fixed cone angle. The effect of contraction ratio Dx/D, which is defined as the ratio between the vortex finder diameter and the cone diameter, on the turbulent kinetic energy and the velocity components also was investigated. As the contraction ratio decreases, the maximum value of the turbulent kinetic energy and the tangential and axial velocity components increases. The pressure drop was fitted into a correlation as a function of dimensionless quantities (Re, Dx/D, and lc/D) for each design, so that the designers could select the appropriate dimensions according to their design limitations.  相似文献   

17.
Using an old M. Krein’s result and a result concerning symmetric spaces from [S. Radenovi?, Z. Kadelburg, Quasi-contractions on symmetric and cone symmetric spaces, Banach J. Math. Anal. 5 (1) (2011), 38-50], we show in a very short way that all fixed point results in cone metric spaces obtained recently, in which the assumption that the underlying cone is normal and solid is present, can be reduced to the corresponding results in metric spaces. On the other hand, when we deal with non-normal solid cones, this is not possible. In the recent paper [M.A. Khamsi, Remarks on cone metric spaces and fixed point theorems of contractive mappings, Fixed Point Theory Appl. 2010, 7 pages, Article ID 315398, doi:10.1115/2010/315398] the author claims that most of the cone fixed point results are merely copies of the classical ones and that any extension of known fixed point results to cone metric spaces is redundant; also that underlying Banach space and the associated cone subset are not necessary. In fact, Khamsi’s approach includes a small class of results and is very limited since it requires only normal cones, so that all results with non-normal cones (which are proper extensions of the corresponding results for metric spaces) cannot be dealt with by his approach.  相似文献   

18.
In 2000, Branciari replaced the triangle inequality by a more general one which today is known as the rectangular inequality and introduced the notion of generalized metric space or rectangular metric space. Subsequently Azam, Arshad, and Beg introduced the concept of rectangular cone metric space and proved fixed point results for Banach-type contractions in rectangular cone metric spaces. In this paper, we establish fixed point results for mappings that satisfy a contractive condition of Perov type in rectangular cone metric spaces.  相似文献   

19.
In this paper, we first discuss the geometric properties of the Lorentz cone and the extended Lorentz cone. The self-duality and orthogonality of the Lorentz cone are obtained in Hilbert spaces. These properties are fundamental for the isotonicity of the metric projection with respect to the order, induced by the Lorentz cone. According to the Lorentz cone, the quasi-sublattice and the extended Lorentz cone are defined. We also obtain the representation of the metric projection onto cones in Hilbert quasi-lattices. As an application, solutions of the classic variational inequality problem and the complementarity problem are found by the Picard iteration corresponding to the composition of the isotone metric projection onto the defining closed and convex set and the difference in the identity mapping and the defining mapping. Our results generalize and improve various recent results obtained by many others.  相似文献   

20.
In this paper, firstly, a new notion of generalized cone convex set-valued map is introduced in real normed spaces. Secondly, a property of the generalized cone convex set-valued map involving the contingent epiderivative is obtained. Finally, as the applications of this property, we use the contingent epiderivative to establish optimality conditions of the set-valued optimization problem with generalized cone convex set-valued maps in the sense of Henig proper efficiency. The results obtained in this paper generalize and improve some known results in the literature.  相似文献   

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