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1.
剩余格与正则剩余格的特征定理   总被引:53,自引:1,他引:52       下载免费PDF全文
裴道武 《数学学报》2002,45(2):271-278
本文进一步研究了具有广泛应用的一类模糊逻辑代数系统——剩余格,并引入了正则剩余格的概念,对剩余格与正则剩余格的定义进行了讨论,给出了剩余格与正则剩余格的特征定理,其中包含剩余格与正则剩余格的等式特征,从而这两个格类都构成簇.本文还讨论了剩余格与正则剩余格公理系统的独立性,以及它们与相近代数结构的关系.  相似文献
2.
E-Convex Sets, E-Convex Functions, and E-Convex Programming   总被引:33,自引:0,他引:33  
A class of sets and a class of functions called E-convex sets and E-convex functions are introduced by relaxing the definitions of convex sets and convex functions. This kind of generalized convexity is based on the effect of an operator E on the sets and domain of definition of the functions. The optimality results for E-convex programming problems are established.  相似文献
3.
Wiener Index of Hexagonal Systems   总被引:18,自引:0,他引:18  
The Wiener index W is the sum of distances between all pairs of vertices of a (connected) graph. Hexagonal systems (HS's) are a special type of plane graphs in which all faces are bounded by hexagons. These provide a graph representation of benzenoid hydrocarbons and thus find applications in chemistry. The paper outlines the results known for W of the HS: method for computation of W, expressions relating W with the structure of the respective HS, results on HS's extremal w.r.t. W, and on integers that cannot be the W-values of HS's. A few open problems are mentioned. The chemical applications of the results presented are explained in detail.  相似文献
4.
In this work, we first study in detail the formulation of the primal-dual interior-point method for linear programming. We show that, contrary to popular belief, it cannot be viewed as a damped Newton method applied to the Karush-Kuhn-Tucker conditions for the logarithmic barrier function problem. Next, we extend the formulation to general nonlinear programming, and then validate this extension by demonstrating that this algorithm can be implemented so that it is locally and Q-quadratically convergent under only the standard Newton method assumptions. We also establish a global convergence theory for this algorithm and include promising numerical experimentation.The first two authors were supported in part by NSF Cooperative Agreement No. CCR-8809615, by Grants AFOSR 89-0363, DOE DEFG05-86ER25017, ARO 9DAAL03-90-G-0093, and the REDI Foundation. The fourth author was supported in part by NSF DMS-9102761 and DOE DE-FG02-93ER25171. The authors would like to thank Sandra Santos for painstakingly proofreading an earlier verion of this paper.  相似文献
5.
6.
Filled functions for unconstrained global optimization   总被引:14,自引:0,他引:14  
This paper is concerned with filled function techniques for unconstrained global minimization of a continuous function of several variables. More general forms of filled functions are presented for smooth and non-smooth optimization problems. These functions have either one or two adjustable parameters. Conditions on functions and on the values of parameters are given so that the constructed functions have the desired properties of filled functions.  相似文献
7.
Generalized Semicontinuity and Existence Theorems for Cone Saddle Points   总被引:11,自引:0,他引:11  
This paper is concerned with existence theorems for generalized saddle points (cone saddle points) of vector-valued functions. A concept of lower semicontinuity for vector-valued functions is introduced and its properties are investigated. Previous results of the author are extended by using the lower semicontinuity. Accepted 26 April 1996  相似文献
8.
F-互补问题及其与极小元问题的等价性   总被引:11,自引:1,他引:10       下载免费PDF全文
本文在Banach空间中引进了 F-互补问题,讨论了这一问题解的存在性,在向量格中,给出了F-互补问题的可行集是 ∧ -子格的条件,研究了F-互补问题与最小元问题的等价性。  相似文献
9.
On the Generalized Drazin Inverse and Generalized Resolvent   总被引:11,自引:0,他引:11  
We investigate the generalized Drazin inverse and the generalized resolvent in Banach algebras. The Laurent expansion of the generalized resolvent in Banach algebras is introduced. The Drazin index of a Banach algebra element is characterized in terms of the existence of a particularly chosen limit process. As an application, the computing of the Moore-Penrose inverse in >C *-algebras is considered. We investigate the generalized Drazin inverse as an outer inverse with prescribed range and kernel. Also, 2 × 2 operator matrices are considered. As corollaries, we get some well-known results.  相似文献
10.
Explicit Stability Zones for Cournot Game with 3 and 4 Competitors   总被引:10,自引:0,他引:10  
The dynamical system of 3 and 4 competitors in a Cournot game is studied. The stability of its fixed points (Nash-equilibria) are also investigated. The stable and unstable regions are explicitly shown. The bifurcation characteristics are found. Periodic orbits with different periods 7, 25, 18, 13, 17 etc., are detected in both cases. The study of these models is very rich in bifurcation phenomena.  相似文献
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