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1.
针对如何对区间值模糊产生式规则赋予合理权值的问题,将OWA算子引入到区间值模糊推理中。介绍一种基于OWA算子的区间值赋权方法,根据此方法给出区间值模糊集上的加权模糊产生式规则的推理算法。在采用该算法的过程中,为合理地计算输入事实与规则前件的匹配程度,引入基于OWA算子的区间值模糊匹配函数值和总体贴近度的计算方法。实例分析表明了所给出的区间值模糊推理算法的有效性和可行性。  相似文献   

2.
基于区间值加权模糊推理的访问控制模型   总被引:1,自引:0,他引:1  
普适计算已被国内外学术界和工业界公认为未来计算的主流模式,其安全问题是信息安全的一个基础问题。传统的访问控制模型从系统的角度出发保护资源,在进行权限的控制时没有考虑上下文信息等因素。为了满足普适计算环境下访问控制策略的动态自适应性以及上下文信息的模糊不确定性,应用模糊集合理论与模糊推理方法,提出一种基于区间值加权模糊推理的访问控制模型;给出加权模糊匹配函数公式与区间值加权模糊推理方法,实现访问控制策略与实际安全需求的一致性。  相似文献   

3.
基于扩展的带标识的Petri网的加权模糊推理   总被引:1,自引:0,他引:1  
孙晓玲  王宁 《计算机仿真》2009,26(6):175-178,236
为了更加高效计算,并且更加便利地进行加权模糊推理来获得更多的有关加权模糊产生式规则的信息,提出一种某些库所中带有标识的模糊Petri网模型来进行加权模糊推理(WFR).用来标记模糊Petrl网运行的托肯值已经从[0,1]上的实数扩展到了模糊集合.提到的加权模糊推理(WFR)包括了局部权值,确定性因子和阈值等几种知识表示参数,参数用模糊数表示,通过提出的计算模糊推理结果的方法,可以更加高效地计算出最终的推理结果.  相似文献   

4.
一种基于区间值模糊推理的控制器设计   总被引:4,自引:0,他引:4  
本文在区间值模糊匹配推理基础上,设计了一种区间值模糊控制器。为了应用区间值模糊匹配推理方法,文中给出了一种清晰量的区间值模糊化方法,最后用实例说明区间值模糊控制器设计过程以及给出Matlab仿真控制效果。  相似文献   

5.
在深入分析已有的基于相似度的模糊推理算法的基础上,针对其计算复杂、未考虑规则前件权重及规则激活方法可能导致结论不全面的问题,提出一种基于综合相似度的区间值模糊推理算法。引入综合相似度、规则阈值、规则可信度等概念,给出新的模糊规则激活方法及推理结论可信度的计算方法。通过算例说明了新方法在多重多维模糊推理的情况下具有还原性,且计算简单,适用于实际应用。  相似文献   

6.
第一个处理模糊规则的推理模型是L.A.Zadeh的合成推理模型(CRI,Compositional Rule of Inference),并且是最重要的推理机制之一.很多文献研究了CRI法的推广以及满足不同要求的算子的合理选择.文章对直觉区间值模糊推理的CRI算法进行了一般研究,讨论了满足剩余原理的直觉区间值模糊三角模与直觉区间值模糊剩余蕴涵.由于一般形式的直觉区间值模糊推理均可以通过一定的处理方式转化为基本形式的MP(Modus Ponens)或MT(Modus Tollens)问题,所以文章仅就两种最简单的推理形式进行讨论,分别给出直觉区间值模糊环境下的MP和MT问题的CRI问题的一般形式,着重讨论其还原条件,给出还原准则.  相似文献   

7.
本文引入有序权聚类算子(OWA)到区间值模糊集合的相似度度量中,提出了一种改进的双向模糊推理 算法。为采用此算法,文中给出了区间模糊集的加权匹配方向函数,最后通过一个实例说明算法如何灵活地 体现决策者的决策倾向。  相似文献   

8.
应用带标识的模糊Petri网的知识表示方法   总被引:2,自引:1,他引:1       下载免费PDF全文
提出一种在某些库所中带有标识的模糊Petri网模型来进行知识表示。为了获得更多的加权模糊产生式规则的信息,在知识表示的过程中考虑了权值,确定性因子,阈值等参数。这种模糊Petri网充分利用了Petri网的并行处理能力。随着带标识的模糊Petri网的运行,网中标识的变化可以标记加权模糊推理的运行。通过文中给出的基于相似性测度的计算方法可以更加高效地计算出多层加权模糊推理的推理结果。  相似文献   

9.
普适计算环境下基于信任度的模糊自适应访问控制模型*   总被引:1,自引:0,他引:1  
在信任模型基础上,提出一种基于信任度的模糊自适应访问控制模型。该模型扩展信任度的概念,建立权限的区间值模糊策略规则,通过对与主体相关的上下文信息的模糊推理实现授权的有效控制。描述模型的构成要素,研究模型的区间值模糊推理算法,为解决普适计算环境下动态访问控制授权问题提供了一定的技术手段。  相似文献   

10.
基于模糊推理模型的水泥粉磨专家控制系统研究   总被引:1,自引:0,他引:1  
针对水泥粉磨这一类难用准确的数学模型来描述以及常规模糊控制器的控制效果不理想等问题,通过将模糊控制技术与专家系统的有机融合,提出了基于模糊推理的贴近度决策方法,建立了模糊控制规则模型,解决了模糊推理的规则匹配问题,并给出了控制结论的化优化求解模型。实验结果表明该方法改善了负荷控制性能,提高了产品质量和磨机生产效率。  相似文献   

11.
Robustness of interval-valued fuzzy inference   总被引:1,自引:0,他引:1  
Since interval-valued fuzzy set intuitively addresses not only vagueness (lack of sharp class boundaries) but also a feature of uncertainty (lack of information), interval-valued fuzzy reasoning plays a vital role in intelligent systems including fuzzy control, classification, expert systems, and so on. To utilize interval-valued fuzzy inference better, it is very important to study the fundamental properties of interval-valued fuzzy inference such as robustness. In this paper, we first discuss the robustness of interval-valued fuzzy connectives. And then investigate the robustness of interval-valued fuzzy reasoning in terms of the sensitivity of interval-valued fuzzy connectives and maximum perturbation of interval-valued fuzzy sets. These results reveal that the robustness of interval-valued fuzzy reasoning is directly linked to the selection of interval-valued fuzzy connectives.  相似文献   

12.
In this paper, we develop a series of induced generalized aggregation operators for hesitant fuzzy or interval-valued hesitant fuzzy information, including induced generalized hesitant fuzzy ordered weighted averaging (IGHFOWA) operators, induced generalized hesitant fuzzy ordered weighted geometric (IGHFOWG) operators, induced generalized interval-valued hesitant fuzzy ordered weighted averaging (IGIVHFOWA) operators, and induced generalized interval-valued hesitant fuzzy ordered weighted geometric (IGIVHFOWG) operators. Next, we investigate their various properties and some of their special cases. Furthermore, some approaches based on the proposed operators are developed to solve multiple attribute group decision making (MAGDM) problems with hesitant fuzzy or interval-valued hesitant fuzzy information. Finally, some numerical examples are provided to illustrate the developed approaches.  相似文献   

13.
本文首先提出群区间直觉模糊有序加权几何(groupinterval-valuedintuitionistic fuzzy orderedweighted geometric,GIVIFOWG)算子和群区间直觉模糊有序加权平均(group interval-valued intuitionistic fuzzy ordered weighted averaging,GIVIFOWA)算子.利用GIVIFOWG算子或GIVIFOWA算子聚集群的决策矩阵以获得方案在属性上的综合区间直觉模糊决策矩阵(collectiveinterval-valuedintuitionistic fuzzy decision-matrix,CIVIFDM).然后定义了一个考虑犹豫度的区间直觉模糊熵(interval-valuedintuitionistic fuzzyentropy,IVIFE);通过熵衡量每个属性所含的信息来求解属性权重.最后,提出基于可能度的接近理想解的区间排序法(interval technique for order preference by similarity to an ideal solution,ITOPSIS)和区间得分函数法.在ITOPSIS法中,依据区间距离公式计算候选方案和理想方案的属性加权区间距离,进而采用ITOPSIS准则对各方案进行排序;在区间得分函数法中,算出CIVIFDM中各方案的得分值以及精确值,然后利用区间得分准则对各方案进行排序.实验结果验证了决策方法的有效性和可行性.  相似文献   

14.
二型直觉模糊集   总被引:1,自引:0,他引:1  
赵涛  肖建 《控制理论与应用》2012,29(9):1215-1222
二型模糊集和直觉模糊集都具有很强的实际应用背景.二型模糊集增强了系统处理不确定性的能力,直觉模糊集为解决人们判断问题所出现的犹豫信息提供了理论依据.本文在二型模糊集和直觉模糊集的基础上,给出了二型直觉模糊集的概念,证明了二型直觉模糊集是一型模糊集、直觉模糊集、区间值模糊集、区间值直觉模糊集的广义形式,讨论了二型直觉模糊集的基本运算和二型直觉模糊关系.最后,研究了基于二型直觉模糊理论的近似推理,并实例说明了二型直觉模糊集的实际应用背景.  相似文献   

15.
Q-rung orthopair fuzzy sets (q-ROFSs), initially proposed by Yager, are a new way to reflect uncertain information. The existing intuitionistic fuzzy sets (IFSs) and Pythagorean fuzzy sets are special cases of the q-ROFSs. However, due to insufficiency in available information, it is difficult for decision makers to exactly express the membership and nonmembership degrees by crisp numbers, and interval membership degree and interval nonmembership degree are good choices. In this paper, we propose the concept of interval-valued q-rung orthopair fuzzy set (IVq-ROFS) based on the ideas of q-ROFSs and some operational laws of q-rung orthopair fuzzy numbers (q-ROFNs). Then, some interval-valued q-rung orthopair weighted averaging operators are presented based on the given operational laws of q-ROFNs. Further, based on these operators, we develop a novel approach to solve multiple-attribute decision making (MADM) problems under interval-valued q-rung orthopair fuzzy environment. Finally, a numerical example is provided to illustrate the application of the proposed method, and the sensitivity analysis is further carried out for the parameters.  相似文献   

16.
Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is presented in this paper, in which attribute reduction is a key to obtain the simplified knowledge model. Through defining dependency and inclusion functions, algorithms for attribute reduction and rule extraction are obtained. The approximation inference plays an important role in the development of the fuzzy system. To improve the inference mechanism, we provide a method of similaritybased inference in an interval-valued fuzzy environment. larity based approximate reasoning, an inference result is Combining the conventional compositional rule of inference with simideduced via rule translation, similarity matching, relation modification, and projection operation. This approach is applied to the problem of predicting welding distortion in marine structures, and the experimental results validate the effectiveness of the proposed methods of knowledge modeling and similarity-based inference.  相似文献   

17.
The fuzzy rough set model and interval-valued fuzzy rough set model have been introduced to handle databases with real values and interval values, respectively. Variable precision rough set was advanced by Ziarko to overcome the shortcomings of misclassification and/or perturbation in Pawlak rough sets. By combining fuzzy rough set and variable precision rough set, a variety of fuzzy variable precision rough sets were studied, which cannot only handle numerical data, but are also less sensitive to misclassification. However, fuzzy variable precision rough sets cannot effectively handle interval-valued data-sets. Research into interval-valued fuzzy rough sets for interval-valued fuzzy data-sets has commenced; however, variable precision problems have not been considered in interval-valued fuzzy rough sets and generalized interval-valued fuzzy rough sets based on fuzzy logical operators nor have interval-valued fuzzy sets been considered in variable precision rough sets and fuzzy variable precision rough sets. These current models are incapable of wide application, especially on misclassification and/or perturbation and on interval-valued fuzzy data-sets. In this paper, these models are generalized to a more integrative approach that not only considers interval-valued fuzzy sets, but also variable precision. First, we review generalized interval-valued fuzzy rough sets based on two fuzzy logical operators: interval-valued fuzzy triangular norms and interval-valued fuzzy residual implicators. Second, we propose generalized interval-valued fuzzy variable precision rough sets based on the above two fuzzy logical operators. Finally, we confirm that some existing models, including rough sets, fuzzy variable precision rough sets, interval-valued fuzzy rough sets, generalized fuzzy rough sets and generalized interval-valued fuzzy variable precision rough sets based on fuzzy logical operators, are special cases of the proposed models.  相似文献   

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