稀疏规则库条件下的模糊推理方法

当模糊规则库是稀疏型时,利用Kóczy线性插值推理方法不能保证推理结论的正规性和凸性,为了解决这一问题,石岩曾提出了插值推理方法的推理条件,当满足这些条件时利用Kóczy线性插值推理方法得到的推理结论也满足正规性和凸性;但是这些条件却限制了模糊推理系统的应用,而且如果多次推理中在同一输入点遇到稀疏情况,必须进行相同的计算才能得到正确的推理结果,这样增加了系统的计算量,降低了系统的速度和效率.因此提出了一种新的稀疏模糊推理方法,不仅能够简单的给出正确的推理结果,还能在相应的位置增加规则,提高规则库的紧密程度.     

Some properties of fuzzy reasoning in propositional fuzzy logic systems

In order to analyze the logical foundation of fuzzy reasoning, this paper first introduces the concept of generalized roots of theories in ?ukasiewicz propositional fuzzy logic ?uk, Gödel propositional fuzzy logic Göd, Product propositional fuzzy logic Π, and nilpotent minimum logic NM (the R₀-propositional fuzzy logic L^∗). Next, it is proved that all consequences of a theory Γ, named D(Γ), are completely determined by its generalized root whenever Γ has a generalized root. Moreover, it is proved that every finite theory Γ has a generalized root, which can be expressed by a specific formula. Finally, we demonstrate the existence of a non-fuzzy version of Fuzzy Modus Ponens (FMP) in ?uk, Göd, Π and NM (L^∗), and we provide its numerical version as a new algorithm for solving FMP.     

A fuzzy logic system based on Schweizer-Sklar t-norm

In recent years, the basic research of fuzzy logic and fuzzy reasoning is growing ac- tively day by day, such as the basic logic system BL proposed by Hajek[1]; fuzzy logic system MTL proposed by Esteva and Godo[2]; fuzzy reasoning, implication operators …     

A new generalized improved score function of interval-valued intuitionistic fuzzy sets and applications in expert systems

The objective of this paper is divided into two folds. Firstly, a new generalized improved score function has been presented in the interval-valued intuitionistic fuzzy sets (IVIFSs) environment by incorporating the idea of weighted average of the degree of hesitation between their membership functions. Secondly, an IVIFSs based method for solving the multi-criteria decision making (MCDM) problem has been presented with completely unknown attribute weights. A ranking of the different attributes is based on the proposed generalized improved score functions and the sensitivity analysis on the ranking of the system has been done based on the decision-making parameters. An illustrative examples have been studied to show that the proposed function is more reasonable in the decision-making process than other existing functions.     

改进的模糊逻辑偏微分方程去噪方法

在研究图像噪声过滤时,为了既有效地去除噪声,又能够较好地保持图像边缘和重要的细节信息,将模糊逻辑思想与PM方法相结合,提出了一种对噪声图像更有效的基于模糊逻辑的偏微分方程去噪算法。该算法把PM方法中扩散方程的扩散系数看作像素梯度对于图像平滑区域的模糊隶属度函数,并通过定义合理的模糊隶属度函数,使得对不同的像素梯度大小采用不同的扩散系数。仿真实验表明,此算法在去除噪声的同时,能更好地保持图像的边缘细节,具有较好的处理效果。     

面向后件集的模糊推理机制: 用于区间型type-2模糊逻辑系统

目前,大多数模糊推理都是利用t-范数和t-余范数或其改进形式对连接词进行建模,这些模型不能将模糊规则中前件集与后件集之间的相关性信息引入到模糊推理过程,这会丢失蕴含在规则中的一些信息甚至导致推理结果与实际经验严重不符.为解决此问题,本文首先引入模糊集合面向对象变换的概念,并将其推广,建立了合成type-2模糊集合模型.基于此模型,针对区间型type-2模糊逻辑系统,提出一种面向后件集的模糊推理机制,该机制能将前件集与后件集的相关性信息(包括清晰数和模糊数两种情形)引入到模糊推理过程.仿真结果表明,该方法能捕获到模糊规则中更多的不确定性信息,并为模糊逻辑系统的设计提供更大的自由度.     

基于模糊逻辑的Ad Hoc网络信任模型研究

为了研究Ad Hoc网络中节点间的信任关系，借助于模糊逻辑的知识，提出了一种基于模糊逻辑的Ad Hoc网络信任模型。该信任模型考虑了影响Ad Hoc网络信任的几个因素，并用模糊逻辑的方法来处理它们以得到节点的信任值。由仿真示例可以看出，该模型符合现实中的信任行为。     

基于直觉模糊蕴涵式运算直觉模糊近似推理方法*

在基于扩展二值逻辑的直觉模糊蕴涵式运算方法的基础上,提出了一种新的直觉模糊近似推理方法,该方法系统而全面地概括了直觉模糊集的蕴涵关系和直觉模糊近似推理方法。通过实例验证了所提出的直觉模糊近似推理方法的有效性和正确性。     

一类模糊系统的逼近问题

对于一类模糊系统，首次给出了它们可在紧论域上以任意要求的精度逼近任意C^1函数的构造性充分条件，同时导出了可用于计算所需模糊规则条数的显式公式，对于多项式函数情形，证明了所给结果比献[1]中结果保守性要小。     

基于直觉模糊推理的多属性群决策方法研究*

针对属性取值以直觉模糊数形式给出的多属性决策问题,提出了基于直觉模糊推理的多属性群决策方法。首先针对专家的评价信息构建直觉决策推理规则,然后根据规则之间的关系给出了决策推理模型,进而给出了基于直觉模糊推理的决策方法;最后通过购房实例验证了该方法的正确性和有效性。     

动态模糊逻辑关系学习

提出一种动态模糊逻辑（DFL）关系学习方法,该方法处理了动态模糊谓词和学习不同种类的动态模糊一阶规则的程序。针对不同类型的规则,定义了相关的置信度来考虑算法中的动态模糊谓词。通过实例验证了算法的有效性。     

基于模糊决策过程的模糊计算树逻辑模型检测

针对由数据表述产生的不确定性模糊系统的模型检测问题,给出模糊计算树逻辑模型检测算法。首先,引入模糊决策过程作为此类系统的模型,其最大特点是在迁移过程中对动作的不确定性选择和状态表述的模糊性。然后,在模糊决策过程基础上,给出模糊计算树逻辑的语法和语义。最后,给出模糊计算树逻辑模型检测算法,该算法是将模糊计算树逻辑模型检测问题转换为模糊矩阵的合成运算,其优势是时间复杂度低、计算过程较为简洁。     

模糊控制在垂直切换判决算法中的应用

为了满足用户的各种通信需求,垂直切换判决算法中考虑的因素越来越多,判决因素的增加,使得切换判决所需的时间延长,不能够实现快而有效的切换判决,影响了移动终端的实用性。并行模糊控制系统使得各判决因素同时进行模糊推理且大大减少模糊规则的数量,降低了切换判决的时延。把网络可用带宽、用户移动速度及网络的服务费用作为判决因素进入并行模糊控制系统,通过用户服务类型的不同,对各判决因素动态地计算相应的权值,同时各判决因素通过模糊控制系统的输出值与权值对应相乘相加,从而得到最优的切换目标网络。仿真结果表明,该算法增强了切换的准确性,减少了不必要的切换,增强了系统性能。     

泛逻辑学中UB代数系统的fuzzy滤子

文献[2]给出了理想状态下泛逻辑学的形式演绎系统!,证明了此系统是可靠的。文献[3]提出了在理想状态(h=k=0.5)下泛逻辑学对应的代数系统-UB代数。文献[5]研究了泛逻辑学中UB代数系统的若干性质。在文献[3,5]的基础上,进一步讨论了UB代数fuzzy滤子与商代数。     

Fuzzy operator logic and fuzzy resolution

There have been only few attempts to extend fuzzy logic to automated theorem proving. In particular, the applicability of the resolution principle to fuzzy logic has been little examined. The approaches that have been suggested in the literature, however, have made some semantic assumptions which resulted in limitations and inflexibilities of the inference mechanism. In this paper we present a new approach to fuzzy logic and reasoning under uncertainty using the resolution principle based on a new operator, the fuzzy operator. We present the fuzzy resolution principle for this logic and show its completeness as an inference rule.     

Fault detection in non-linear systems based on type-2 fuzzy logic

This paper presents a new method for fault detection (FD) based on interval type-2 fuzzy sets. The main idea is based on a confident span using interval type-2 fuzzy systems. An estimate for upper and lower bounds of output has been taken using the designing of an optimal fuzzy system through clustering. Finally the method has been tested in two non-linear systems, a two-tank with a fluid flow and pH neutralisation process, and it is compared with a well-known method named ANFIS. Furthermore, the mathematical model and the results of simulations prove the effectiveness, usefulness and applications of our new method.     

Polynomial regression interval-valued fuzzy systems

In recent years, the type-2 fuzzy sets theory has been used to model and minimize the effects of uncertainties in rule-base fuzzy logic system (FLS). In order to make the type-2 FLS reasonable and reliable, a new simple and novel statistical method to decide interval-valued fuzzy membership functions and probability type reduce reasoning method for the interval-valued FLS are developed. We have implemented the proposed non-linear (polynomial regression) statistical interval-valued type-2 FLS to perform smart washing machine control. The results show that our quadratic statistical method is more robust to design a reliable type-2 FLS and also can be extend to polynomial model.     

A fuzzy rule-based generation algorithm in interval type-2 fuzzy logic system for fault prediction in the early phase of software development

Reliability, a measure of software, deals in total number of faults count up to a certain period of time. The present study aims at estimating the total number of software faults during the early phase of software life cycle. Such estimation helps in producing more reliable software as there may be a scope to take necessary corrective actions for improving the reliability within optimum time and cost by the software developers. The proposed interval type-2 fuzzy logic-based model considers reliability-relevant software metric and earlier project data as model inputs. Type-2 fuzzy sets have been used to reduce uncertainties in the vague linguistic values of the software metrics. A rule formation algorithm has been developed to overcome inconsistency in the consequent parts of large number of rules. Twenty-six software project data help to validate the model, and a comparison has been provided to analyse the proposed model’s performance.     

一种改进的区间二型模糊控制器设计

针对二型模糊控制器设计中出现的降型计算方法损失不确定性信息的问题,提出一种改进的区间二型模糊控制器．该控制器在充分利用二型模糊推理结果的前提下,对区间模糊输出进行再次优化,其优化指标可直接与被控系统性能相关,由此可得到更有利于提高系统整体性能的准确输出量．最后,将改进的控制器用于汽车非线性悬架系统的控制,仿真结果验证了所提出方法的有效性．     

基于规则插入的自适应模糊控制器的设计

提出一种为模糊控制器系统开发有效规则的自适应模糊控制器的设计方法.该方法首先基于两个基本的If-then模糊规则,然后插入多个新If_then模糊规则,其合成的模糊规则的输入_输出映射保持不变,且其隶属函数的参数在线约束为最小化成本函数,最后以最典型的非线性和延迟系统模型为例进行仿真实验,结果证明了该设计方法的有效性.