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1.
根据实际中经常遇到的信息传递情况:一是我们不能丢失任何可能有用的信息,以免造成损失;二是被传递的概念是双向动态变化的模糊数据,三是信息传递者的知识不同,接收到的数据信息不一样。本文利用具有动态特性的双向S-粗模糊集构建了一种新的动态模糊数据粗传递模型-上近似动态模糊数据粗传递模型,分析了信息传递者的知识对模糊数据粗传递的影响,建立了知识依赖、知识等价、知识独立与传递过程中动态模糊数据变化的关系,得到了动态模糊数据在传递过程中保持不变、发生增益的条件,给出了动态模糊粗传递数据不变定理及数据增益定理,最后给出了动态模糊粗传递模型在风险投资管理系统中应用,制定了符合实际的投资决策。动态模糊粗传递是双向S-粗模糊集的一种新的应用。  相似文献   

2.
根据实际中的三种信息传递情况,本文利用粗糙模糊集、模糊子集、截集等理论讨论了λ-模糊粗传递模型的特性,得到了λ-模糊粗传递模型与模糊粗传递模型的关系,给出了两种分解定理.以此为基础,分析了λ-模糊粗传递模型中信息的变化情况,给出了信息精确传递的条件,进一步得出了提高信息传递精确性的方法.λ-模糊粗传递是粗糙模糊集的一种新的应用.  相似文献   

3.
粗集理论对知识进行了形式化定义,它为处理不确定,不完整的海量数据知识提供了一套严密的数据分析处理工具.但粗集概念及运算的代数意义表示往往不易被人理解.本文针对于此。在知识库中提出了知识的信息熵问题,证明了知识的某些信息表示与其代数表示是等价的,最后还讨论了知识库上的粗动力系统的一些性质。  相似文献   

4.
粗糙子群和粗糙子环   总被引:3,自引:0,他引:3  
文[1]研究了半群中的理想,首次提出了粗半群和粗理想的概念.本文继续研究了群中的粗糙子群和粗正规子群.同时,在环中引入了粗子环的概念.最后,研究了粗糙集的同态问题.  相似文献   

5.
函数单向S粗集对偶(dual offunction one direction singular rough sets)是函数S粗集的基本形式之一,函数单向S-粗集对偶具有动态特性与规律(函数)特性.函数S粗集(function singular rough sets)是把函数概念引入到S粗集内(singular rough sets)改进S粗集得到的把导数概念与函数单向S粗集对偶交叉、渗透给出粗边际规律F-粗边际规律概念;给出粗边际规律F-粗边际规律特征;给出F-粗边际规律与粗边际规律的关系;给出F-粗边际规律在经济信息系统中的应用  相似文献   

6.
引入幂序列单增模糊矩阵的概念并讨论它的性质, 给出一种基于幂序列单增模糊矩阵构造的求模糊关系矩阵传递闭包的新算法; 并通过与现有的两种传递闭包求解算法的比较分析, 借助实例说明了算法的有效性和简洁性.  相似文献   

7.
覆盖S-粗集模型的性质   总被引:2,自引:1,他引:1  
讨论基于覆盖理论的S-粗集模型的性质,给出了S-粗集生成的拓扑结构,证明了覆盖S-粗集模型与自反、传递关系下的S-粗集模型是等价的。  相似文献   

8.
一种求布尔矩阵传递闭包的基于自反矩阵构造的平方算法   总被引:2,自引:0,他引:2  
首先,介绍布尔矩阵传递闭包的概念及计算问题;随后,分析布尔矩阵的传递闭包和由该布尔矩阵与单位矩阵取并所得到的自反矩阵的传递闭包之间的关系;最后,利用上述结果给出一种求解布尔矩阵传递闭包的基于自反矩阵构造的平方算法,并通过实例说明了其具体计算过程.  相似文献   

9.
在前面已讨论过的静态粗信息矩阵数量特征(粒度、精度)基础上,利用动态粗糙集理论,进一步给出动态粗信息粒度矩阵的三种形式,系统地讨论了静态、动态系统的粗信息粒度矩阵的特征及其关系定理,这一研究不仅完善了粗信息矩阵这一新的研究方向内容,而且为动态系统的知识挖掘提供了一个可靠的依据。  相似文献   

10.
针对S-粗集模型及其现有扩展模型不能有效处理具有动态特性的偏好信息系统这一缺陷,本文提出了一种双向S-变精度优粗集模型,并给出了该模型的一些性质。新模型具有一定的抗数据干扰能力,从而可在动态偏好信息决策系统中获得更加合理的分类;最后给出一个应用实例,验证了新模型的有效性。  相似文献   

11.
A rough posynomial geometric programming is put forward by the author. This model is advantageous for us to consider questions not only from the quantity of aspect, but from the quality because it contains more information than a traditional geometric programming one. Here, a rough convex function concept is advanced in rough value sets on foundation of rough sets and rough convex sets. Besides, a knowledge expression model in rough posynomial geometric programming is established and so is a mathematical one. Thirdly, solution properties are studied in mathematical model of rough posynomial geometric programming, and antinomy of the more-for-less paradox is solved with an arithmetic in rough posynomial geometric programming given, which can be changed into a rough linear programming after monomial rough posynomial geometric programming is solved. Finally, validity in model and algorithm is verified by examples.  相似文献   

12.
知识推理中的冲突消解,不仅受到知识粒度的影响,还与所采用的具体方法有关.首先讨论了应用Rough理论对规则的粒度进行客观刻画,在此基础上采用距离概念构造了刻画规则相近性的规则距离公式,并在公式中引入了Rough理论中属性重要性算子,然后在分析传统冲突消解策略的基础上,提出了知识推理过程中规则集进化的概念,最后通过实例说明了此策略在知识推理中的具体应用.  相似文献   

13.
粗糙不变子群的若干性质与粗糙商群   总被引:1,自引:0,他引:1  
讨论粗糙集理论在代数系统——群上的应用。基于有关粗糙群、粗糙子群和粗糙不变子群的基本概念以及粗糙子群的一些性质和有关粗糙不变子群的定理,讨论了粗糙不变子群的若干性质和粗糙商群的概念,并给出了这些性质的严格证明。  相似文献   

14.
Diverse reduct subspaces based co-training for partially labeled data   总被引:1,自引:0,他引:1  
Rough set theory is an effective supervised learning model for labeled data. However, it is often the case that practical problems involve both labeled and unlabeled data, which is outside the realm of traditional rough set theory. In this paper, the problem of attribute reduction for partially labeled data is first studied. With a new definition of discernibility matrix, a Markov blanket based heuristic algorithm is put forward to compute the optimal reduct of partially labeled data. A novel rough co-training model is then proposed, which could capitalize on the unlabeled data to improve the performance of rough classifier learned only from few labeled data. The model employs two diverse reducts of partially labeled data to train its base classifiers on the labeled data, and then makes the base classifiers learn from each other on the unlabeled data iteratively. The classifiers constructed in different reduct subspaces could benefit from their diversity on the unlabeled data and significantly improve the performance of the rough co-training model. Finally, the rough co-training model is theoretically analyzed, and the upper bound on its performance improvement is given. The experimental results show that the proposed model outperforms other representative models in terms of accuracy and even compares favorably with rough classifier trained on all training data labeled.  相似文献   

15.
Human beings often observe objects or deal with data hierarchically structured at different levels of granulations. In this paper, we study optimal scale selection in multi-scale decision tables from the perspective of granular computation. A multi-scale information table is an attribute-value system in which each object under each attribute is represented by different scales at different levels of granulations having a granular information transformation from a finer to a coarser labelled value. The concept of multi-scale information tables in the context of rough sets is introduced. Lower and upper approximations with reference to different levels of granulations in multi-scale information tables are defined and their properties are examined. Optimal scale selection with various requirements in multi-scale decision tables with the standard rough set model and a dual probabilistic rough set model are discussed respectively. Relationships among different notions of optimal scales in multi-scale decision tables are further analyzed.  相似文献   

16.
不完备信息系统中目前有多种扩充,如基于容差关系的扩充、基于相似关系的扩充等等,但是这些扩充都各自存在局限性。针对这些局限性,引入相对分类错误率的概念,提出了一种基于限制容差关系下的集对变精度粗糙集模型。这就将经典的粗糙集模型和限制容差关系下的集对粗糙集模型进行了推广。然后,讨论了该模型上、下近似算子的一些性质。最后,通过一个具体例子,说明了该模型在不完备信息系统中处理模糊和不确定性知识是可行、有效的。  相似文献   

17.
环中的粗素理想与模糊粗素理想   总被引:2,自引:0,他引:2  
首次提出了环中的粗素理想与模糊粗素理想的概念,并讨论了它的性质及同态问题。  相似文献   

18.
模糊粗糙集及粗糙模糊集的模糊度   总被引:5,自引:0,他引:5  
1965年,Zadeh提出了Fuzzy集理论,1982年,Z.Pawlak提出Rough集理论。将二者结合而形成的模糊粗糙集(FR集)及粗糙模糊集(RF集)近年来越来越受到国际学术界的关注。本文所研究的FR集及RF集的模糊度,是对FR集及RF集模糊程度的一种度量,进而引进了相应的明可夫斯基距离,明可夫斯基模糊度和Shannon模糊度。  相似文献   

19.
集合的粗相似度量   总被引:2,自引:1,他引:1  
在近似空间中,利用粗糙集诱导的模糊集,定义了两个集合间的粗相似度的概念,讨论了其性质,并对四种具体的粗相似度进行了比较。  相似文献   

20.
In this paper, we propose two variations of rough approximable concepts and investigate the order-theoretic properties of the associated concept hierarchies. We first show that every rough pseudo-concept hierarchy is a completely distributive lattice and its completely compact elements are exactly the rough pseudo-concepts generated from individual attributes. Next, we propose the notions of hyper-contexts and hyper-concepts, and prove that they provide an approach to restructuring algebraic domains. Finally, we set hyper-contexts into a category in which hyper-mappings serve as the morphisms. It turns out that this category is precisely equivalent to that of algebraic domains.  相似文献   

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