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61.
知识约简是机器学习,模式识别,信号处理等领域的主要问题之一。本文介绍了基于单调包含度的模糊决策信息系统的知识约简。证明了模糊决策信息系统的约简即是其对应信息系统的约简,从而为该种模糊决策信息系统的知识约简提供了简单直接的方法。 相似文献
62.
63.
(∈,∈∨ q(λ,μ))-凸模糊集 总被引:3,自引:1,他引:2
给出(∈,∈∨q(λ,μ))-凸模糊集的定义,讨论它们的一些基本性质。 相似文献
64.
基于优势关系下不协调目标信息系统的分布约简 总被引:10,自引:0,他引:10
在基于优势关系下的不协调目标信息系统中引入了分布约简和最大分布约简的概念,并讨论了二者之间的关系,而且得到了分布和最大分布约简的判定定理以及辨识矩阵,建立了不协调目标信息系统的分布和最大分布约简的具体方法,同时通过实例验证了该方法的有效性,从而进一步丰富了粗糙集理论。 相似文献
65.
66.
FixedPointTheoremsonaNon-convexSet¥ZhaoXiaoquan(赵晓全)andSunXuesi(孙学思)(DepartmentofMathematica,HarbinInstituteofElectricalTechn... 相似文献
67.
N. J. Wildberger 《Geometriae Dedicata》2007,128(1):145-166
One dimensional metrical geometry may be developed in either an affine or projective setting over a general field using only
algebraic ideas and quadratic forms. Some basic results of universal geometry are already present in this situation, such
as the Triple quad formula, the Triple spread formula and the Spread polynomials, which are universal analogs of the Chebyshev
polynomials of the first kind. Chromogeometry appears here, and the related metrical and algebraic properties of the projective
line are brought to the fore.
相似文献
68.
Combining grey relation and TOPSIS concepts for selecting an expatriate host country 总被引:7,自引:0,他引:7
As international corporate activities increase, their staffing involves more strategic concerns. However, foreign assignments have many differences, and dissatisfaction with the host country is a known cause of expatriate failure. From the point of view of an expatriate candidate, the decision of whether to take an expatriate assignment can be regarded as a FMCDM (fuzzy multiple criteria decision making) problem. This paper describes a fuzzy AHP (fuzzy analytic hierarchy process) to determine the weighting of subjective judgments. Using the Sugeno integral for λ-fuzzy measure, and using the nonadditive fuzzy integral technique to evaluate the synthetic utility values of the alternatives and the fuzzy weights, then the best host country alternative can be derived with the grey relation model. The authors further combine the grey relation model based on the concepts of TOPSIS (technique for order preference by similarity to ideal solution) to evaluate and select the best alternative. A real case of expatriate assignment decision-making was used to demonstrate that the grey relation model combined with the ideas of TOPSIS results in a satisfactory and effective evaluation. 相似文献
69.
We study in this article the polynomial approximation properties of the Quadratic Set Covering problem. This problem, which arises in many applications, is a natural generalization of the usual Set Covering problem. We show that this problem is very hard to approximate in the general case, and even in classical subcases (when the size of each set or when the frequency of each element is bounded by a constant). Then we focus on the convex case and give both positive and negative approximation results. Finally, we tackle the unweighted version of this problem. 相似文献
70.
Several key results for set packing problems do not seem to be easily or even possibly transferable to set covering problems, although the symmetry between them. The goal of this paper is to introduce a nonidealness index by transferring the ideas used for the imperfection index defined by Gerke and McDiarmid [Graph imperfection, J. Combin. Theory Ser. B 83 (2001) 58-78]. We found a relationship between the two indices and the strength of facets defined in [M. Goemans, Worst-case comparison of valid inequalities for the TSP, mathematical programming, in: Fifth Integer Programming and Combinatorial Optimization Conference, Lecture Notes in Computer Science, vol. 1084, Vancouver, Canada, 1996, pp. 415-429; M. Goemans, L.A. Hall, The strongest facets of the acyclic subgraph polytope are unknown, in: Integer Programming and Combinatorial Optimization, Lecture Notes in Computer Science, vol. 1084, Springer, Berlin, 1996, pp. 415-429]. We prove that a clutter is as nonideal as its blocker and find some other properties that could be transferred from the imperfection index to the nonidealness index. Finally, we analyze the behavior of the nonidealness index under some clutter operations. 相似文献