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1.
运用结构元理论来求解具有风险偏好的、带有模糊权值的网络最短路问题.首先,简要介绍模糊结构元及相关定理.之后,提出了组合序,证明组合序是全序.组合序含有参数θ,随着θ的取值范围不同,序反映风险偏好的类型不同.在组合序和相关定理的基础上,证明了模糊网络最短路的判定定理,定理表明:求模糊网络最短路等价求一经典网络最短路,且风险偏好大小由θ的取值来确定.最后,通过一个例子来说明求解过程.  相似文献   

2.
本文是文献的续。对于固定的Frame L,本文证明了每个LF-拟序集可以等价地表示为拟序的层,该结果与L-Fuzzy集的分解和表示定理类似。由这此定理可得出以下结论:一类量化Domain(例如,广义超度量Domain)实际上是将满足一定条件的拟序族进行“粘贴”的结果(按照层论的语言叙述,就是拟序的层),而通常的拟序则是常值拟序层的特例。  相似文献   

3.
本文是文献[4]的续。对于固定的FrameL,本文证明了每个LF-拟序集可以等价地表示为拟序的层,该结果与L-Fuzzy集的分解和表示定理类似。由这此定理可得出以下结论:一类量化Domain(例如,广义超度量Domain)实际上是将满足一定条件的拟序族进行"粘贴"的结果(按照层论的语言叙述,就是拟序的层),而通常的拟序则是常值拟序层的特例。  相似文献   

4.
张宪 《数学学报》2001,44(4):641-646
本文在度量空间中引入半序,证明了半序度量空间中单调增加映射的不动点定理及混合单调映射的耦合不动点定理.  相似文献   

5.
段华贵  李国祯 《数学杂志》2005,25(5):527-532
摘要:本文利用半序方法。研究了一类非线性算子方程的最小最大耦合拟解的存在性。得到几个新的存在性定理,并且改进和推广了中相关结果.  相似文献   

6.
在本文中我们讨论了有限半序集的结构分析,并给出了Dilworth定理的两种新证明。在(一)中我们对半序集引进了独立集(最大不可比集)的概念、度数的概念和顶集的概念。得到了关于半序集结构的分层定理(定理1),并应用顶集的性质对半序集的度数用归纳法给出了Dilworth定理的一种新的证明(定理2)。在(二)中根据半序集的独立集的不同情形,将半序集分成两种类型——A型和B型,证明了任何一个半序集均可表成有限个B型半序集的併(定理3),并据此给出了Dilworth定理的另一种新证明。在(三)中我们应用顶集的性质,对Dilworth的原证明给出了一种简化证明。  相似文献   

7.
尹建东  蔡艳 《应用数学》2012,25(1):20-25
本文引进了一类新的压缩算子,即二元φ-序压缩算子,并且在完备的半序度量空间(其中的半序由φ所导出)上证明了几个二元φ-序压缩算子的不动点定理.本文所得的部分结论推广了最近一些文献中相应的结论.  相似文献   

8.
尹建东  尹国昌 《数学研究》2010,43(2):171-177
2005年,张宪在Banach空间中通过其中的锥所定义的半序引进了序压缩算子,证明了几个相应的定理.但是在一般的度量空间中,能否定义序压缩算子,能否得到类似的结论呢?本文在度量空间X中,通过X上的泛函ψ-所定义的半序,引进了ψ--序压缩算子,并且得到了相应的不动点定理.  相似文献   

9.
引入了偏序半群(S,·,≤)上的半拟序σ及模σ半拟链的概念.通过模σ半拟链,将S的偏序≤扩张为≤*,讨论了(S,*,≤*)是偏序半群的充分条件,并获得了若干理想的结果.特别地,得到了SPO(S)到PO(S)的两个半格同态定理.最后,还给出了S的满足某些给定条件的有限子集在≤*下成链的充要条件.  相似文献   

10.
混合单调算子的不动点定理及其应用   总被引:8,自引:0,他引:8  
颜心力 《应用数学》1991,4(4):107-114
本文在一类新型假设条件下,建立一种新的方法——非对称迭代法,解决了半序空间中惯用的对称迭代法所无能为力的问题.引入半序距离空间概念,对于二元对称压缩算子,给出了几类具有代表性的不动点定理,拓广了Hilbet投影距离概念,获得较以往更为广泛的不动点定理.最后给出若干应用.  相似文献   

11.
After noting factors (concern for others, ignorance, irrationality) accounting for the divergences between preference and happiness, the question of representing the preference of an individual by a utility function is discussed, taking account of lexicographic ordering, imperfect discrimination and the corresponding concepts of semiorder and sub-semiorder. Methods to improve upon the interpersonal comparability of measures of happiness such as pinning down the dividing line of zero happiness and the use of a just perceivable increment of happiness are discussed. The relation of social welfare to individual welfare (i.e. happiness) is then considered. Some reasonable set of axioms ensuring that social welfare is a separable function of and indeed an unweighted sum of individual welfares are reviewed. Finally, happiness is regarded as a function of objective, institutional and subjective factors; an interdisciplinary approach is needed even for an incomplete analysis.  相似文献   

12.
在G?del t-模下,研究了模糊选择函数的半序合理性.首先给出了模糊选择函数的合理性条件FA1.然后研究了该条件与模糊选择函数半序合理性之间的关系,得到了半序合理的一个充分条件.  相似文献   

13.
模糊全半序结构   总被引:3,自引:1,他引:2  
以Fodor公理为基础,给出一类重要的模糊偏好结构——模糊全半序结构的一个较为一般的定义,同时对其性质进行讨论。  相似文献   

14.
在模糊偏好结构下,首先将Schwartz提出的收缩扩张公理模糊化,在选择集为正规模糊集的前提下,研究模糊选择函数Wφ-伪传递及Wφ半序合理的刻画问题。由于模糊化后的条件不再是选择函数伪传递合理的充分条件,因此,文章最后给出新的条件来刻画其合理性。  相似文献   

15.
We provide a condition for an individual preference ordering to be represented by a function measured in terms of a commodity, i.e., for the commodity to be transferable utility. We also consider the relationships between conditions of the preference ordering and the utility function.  相似文献   

16.
Let a finite semiorder, or unit interval order, be given. When suitably defined, its numerical representations are the solutions of a system of linear inequalities. They thus form a convex polyhedron. We show that the facets of the representation polyhedron correspond to the noses and hollows of the semiorder. Our main result is to prove that the system defining the polyhedron is totally dual integral. As a consequence, the coordinates of the vertices and the components of the extreme rays of the polyhedron are all integral multiples of a common value. Total dual integrality is in turn derived from a particular property of the oriented cycles in the directed graph of noses and hollows of a strictly upper diagonal step tableau. Our approach delivers also a new proof for the existence of the minimal representation of a semiorder, a concept originally discovered by Pirlot (Theory Decis 28:109–141, 1990). Finding combinatorial interpretations of the vertices and extreme rays of the representation polyhedron is left for future work.  相似文献   

17.
A poset P=(X,P) is a split semiorder when there exists a function I thatassigns to each x X a closed interval of the real line R and a set of real numbers, with , suchthat x<y in P if and only if and in R. Every semiorder is a split semiorder, and thereare split semiorders which are not interval orders. It is well known thatthe dimension of a semiorder is at most 3. We prove that the dimension of asplit semiorder is at most 6. We note also that some split semiorders havesemiorder dimension at least 3, and that every split semiorder has intervaldimension at most 2.  相似文献   

18.
利用分块矩阵的方法得到了关于半正定矩阵M-P逆的H adam ard积的几个偏序不等式,推广了某些已知的不等式.  相似文献   

19.
本文针对供应商面临生产资金约束的情况,在需求随机条件下研究了由一个风险中性零售商和一个具有风险偏好的供应商组成的二级供应链的协调问题。文章在零售商享有批发价折扣的提前支付和供应商银行信贷两种融资方式下,分别建立了零售商的最优决策模型以及基于M-CVaR测度工具的供应链整体订购决策模型,并给出了采用两种不同融资模式时零售商和供应链整体的最优订购量以及供应链的协调条件,分析了供应商的风险偏好对供应链整体最优决策及协调条件的影响。最后通过算例验证了文章的主要结论。研究表明,当提前支付价格折扣大于临界值时,零售商会选择提前支付货款;提前支付模式下供应链整体的最优订购量大于银行信贷模式;随着供应商的风险偏好由风险规避向风险喜好转变,供应链整体的最优订购量逐渐增大。  相似文献   

20.
In this paper, we extend the knapsack problem to include more realistic situations by treating the rewards (or values) associated with each item included in the solution as random variables with distributions that are known (or may be estimated) rather than known integers, as in the usual formulation. We propose a dynamic programming solution methodology where the usual real-valued return function is replaced by a preference ordering on the distributions of returns from the items selected. In addition to extending previous solutions to the knapsack problem, we demonstrate the selection of a preference ordering criterion and illustrate the conditions required of the ordering to guarantee optimality of the procedure. A sample problem is shown to demonstrate the algorithm, and results of computational experience with 459 problems of varying sizes and parameters are presented.  相似文献   

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