基于证据理论的偏好型直觉模糊群决策方法

针对直觉模糊多属性群决策问题,研究属性和专家权重的确定以及信息的集结方法.利用直觉模糊熵确定属性客观权重,并根据偏好信息确定合理的属性综合权重;在属性层面区分专家权重,将直觉模糊评价值作为Mass函数,构建证据冲突度模型确定专家权重,并利用犹豫度加以修正,避免综合支持度低而对方案排序影响大的专家权重过分削弱;采用证据理论集结决策信息,根据得分值进行方案排序.最后通过算例分析,验证了所提出方法的合理性和有效性.     

基于模糊攻防树和熵权法的工控系统脆弱性量化评估方法

为了提高脆弱性量化评估结果的可靠性,提出一种基于模糊攻防树和熵权法的工控系统脆弱性量化评估方法。该方法以攻击防御树为模型,首先将模糊集合理论与专家评价相结合,然后聚合多位专家对同一安全属模糊评价,在模糊聚合过程中利用模糊距离计算专家模糊评价的偏离度以提高模糊聚合的可靠性,并采用熵权法确定叶子节点量化过程中各安全属性的权重。最后计算叶子节点及攻击序列概率。案例分析表明,该方法能有效提高评估结果的可靠性,为工控系统信息安全防护提供重要依据。     

基于自适应专家权重的信息系统风险评估模型

针对风险评估过程中存在专家权重难以合理设置,评估结果受专家主观性影响大等问题,提出一种基于自适应专家权重的信息系统风险评估模型SAEW-ISRA,给出一种细粒度专家权重自适应调整方法。首先,在评估过程中引入三角模糊数对风险指标属性评分;其次,根据专家评分模糊度描述专家知识量,结合与专家群体评分的距离构建后验权重,可使专家权重自适应调整,同时使用模糊层次分析法构建风险指标权重;然后,提出信息系统风险指标危险度量化方法,可计算风险值;最后,通过某信息系统的风险评估实例验证所提方法能达到更高的评估准确性,同时在一定程度上解决了评估过程中权重不合理问题。     

证据理论与模糊距离不确定性信息融合方法

针对决策支持系统中专家不确定性意见难以融合的问题。提出了一种基于证据理论和模糊距离相结合的决策融合方法。运用模糊距离方法来获得专家的权重和属性指标的相对权重,对专家决策中由于主观认识的局限性带来的不确定性问题进行了研究。运用DS证据理论识别框架计算出概率分配函数,对所有方案进行排序选择,得出最终的决策融合意见。通过实验表明,运用此方法对不确定性信息的融合具有很好的可行性和有效性。     

基于Web的快速原型工艺选择系统

提出一种快速成型(RP)工艺优选方法．该方法综合运用了专家系统和模糊综合评判,通过专家系统初步确定RP候选方案,采用模糊综合评判选择最适合的RP工艺;运用层次分析法,建立了RP工艺优选的多因素、多层次综合评价模型,确定了准则层各个评价因素的权重,并使用Java技术开发了这个工艺选择系统．通过一个典型应用案例展示了该系统的使用方法及其应用效果．结果表明,通过该方法确定的RP工艺更加准确和有效,能够更好地满足用户的需求．     

基于GRA-GCRITIC和改进加权双向投影的区间Fermatean模糊多属性群决策方法

针对司法案件决策环境的复杂性及评价信息的模糊性,提出一种基于GRA-GCRITIC（grey relational analysis-group criteria importance through intercriteria correlation）和改进加权双向投影的区间Fermatean模糊Hamacher-TODIM多属性群决策方法。首先考虑到各位专家对各评价方案下各指标评价信息的差异性,提出一种GRA-GCRITIC方法,该方法将灰色关联融入到CRITIC中,以确定指标综合权重比单一获取的指标权重更加客观可靠。其次,结合信任关系对加权双向投影法进行改进,兼顾主客观关系,利用专家个体与群体评价信息的隶属度及非隶属度矩阵间的相似度得到专家权重。最后,考虑到决策者的损失规避心理,将融合了Hamacher算子的TODIM方法拓展至区间Fermatean模糊环境中,通过具体算例可得到其综合优势度及排序,验证了所提方法的可行性及灵活性。     

AGGREGATING FUZZY OPINIONS IN THE HETEROGENEOUS GROUP DECISION-MAKING ENVIRONMENT

ABSTRACT

We present a new information fusion algorithm for fusing fuzzy opinions in a heterogeneous group decision-making environment. The proposed information fusion algorithm has the following advantages: (1) It uses linguistic quantifiers based on the FN-IOWA operator to flexibly determine the weight w _i of the opinion of each expert E _i for aggregating the experts' fuzzy opinions. (2) The experts' opinions do not necessarily need to have a common intersection. (3) It does not need to use the Delphi method to adjust fuzzy numbers given by experts.     

TRADE‐OFF BETWEEN APPROXIMATION ACCURACY AND COMPLEXITY FOR TS FUZZY MODELS

This paper proposes a transformation method that serves the trade‐off between the modelling complexity and accuracy of multi‐variable Takagi‐Sugeno fuzzy inference operator‐based modelling (TS fuzzy modelling). The relation between the number of fuzzy rules and the modelling accuracy is defined in the paper. The proposed transformation method is capable of finding the minimal number of fuzzy rules for a given accuracy of a given TS fuzzy model. A case study, focusing on a benchmark problem of fault diagnosis, developed in the framework of EC‐founded Research Training Network DAMADICS, of an actuator in a sugar factory, is presented to provide feasibility of the proposed method.     

模糊推理在空调系统故障诊断中的应用

针对空调系统的故障诊断问题及其特点,提出了一种基于诊断知识的模糊描述和模糊推理方法,阐述了空调系统故障诊断专家系统中前向推理、后向推理以及正反向混台推理模糊断言可信度的计算方法,并且给出了相应的实例。     

基于直觉模糊和证据理论的混合型偏好信息集结方法

针对混合型偏好信息的集结问题,利用直觉模糊实现了5类混合型偏好信息的统一,提出利用冲突系数和Jousselme距离综合表示的证据冲突度计算专家权重的方法,最后利用Demsper组合规则对专家权重修正后的证据进行组合.实例分析表明,所提出的偏好信息统一方法能够保持转化前后方案的优先顺序不变,通过专家权重对专家意见的修正使得证据合成结果能体现多数专家的一致意见,具有较高的实用价值.     

A medical decision support system for disease diagnosis under uncertainty

This paper presents a decision support system (DSS) modeled by a fuzzy expert system (FES) for medical diagnosis to help physicians make better decisions. The proposed system collects comprehensive information about a disease from a group of experts. To this aim, a cross-sectional study is conducted by asking physicians’ expertise on all symptoms relevant to a disease. A fuzzy rule based system is then formed based on this information, which contains a set of significant symptoms relevant to the suspected disease. Linguistic fuzzy values are assigned to model each symptom. The input of the system is the severity level of each symptom reported by patients. The proposed FES considers two approaches to account for uncertain inputs from patients. Two case studies on kidney stone and kidney infection were conducted to demonstrate how the proposed method could be used. A group of patients were used to validate the effectiveness of the proposed expert system. The results show that the proposed fuzzy expert system is capable of diagnosing diseases with a high degree of accuracy and precision comparing to a couple of machine learning methods.     

基于关联群广义直觉模糊软集的仿真可信度指标聚合方法

针对仿真可信度主观评估过程存在关联关系时基于独立假设的指标聚合算子失效的问题,以及主观评估时评估专家的判断主观性强且表述能力不足的问题,提出一种基于关联群广义直觉模糊软集的仿真可信度指标聚合方法以及群广义直觉模糊软集关联加权平均聚合算子.结合直觉模糊TOPSIS方法,给出了方法的具体步骤.通过CRH2型高速列车组牵引传动故障注入仿真可信度主观评估实例,验证了所提出方法的可行性和有效性.     

Modeling of a Fuzzy Expert System for Choosing an Appropriate Supply Chain Collaboration Strategy

Nowadays, there has been a great interest for business enterprises to work together or collaborate in the supply chain. It is thus possible for them to gain a competitive advantage in the marketplace. However, determining the right collaboration strategy is not an easy task. Namely, there are several factors that need to be considered at the same time. In this regard, an expert system based on fuzzy rules is proposed to choose an appropriate collaboration strategy for a given supply chain. To this end, firstly, the factors that are significant for supply chain collaboration are extracted via an extensive review of literature. Then, a simulation model of a supply chain is constructed to reveal the performance of collaborative practices under various scenarios. Thereby, it is made possible to establish fuzzy rules for the expert system. Finally, feasibility and practicability of our proposed model is verified with an illustrative case.     

一种基于证据理论和模糊距离的融合方法

针对决策支持系统中专家不确定性意见难以融合的问题。本文提出了一种基于证据理论和模糊距离相结合的决策融合方法。首先运用模糊距离方法来获得专家的权重和属性指标的相对权重,并对专家决策中由于主观认识的局限性带来的不确定性问题进行了研究。然后运用DS证据理论识别框架计算出概率分配函数,并对所有方案进行排序选择,得出最终的决策融合意见。最后,通过实验表明,运用此方法对不确定性信息的融合具有很好的可行性和有效性。     

基于模糊集和DS证据理论的信息安全风险评估方法*

在信息安全风险评估过程中,存在着很多不确定和模糊的因素,针对专家评价意见的不确定性和主观性问题,提出了一种将模糊集理论与DS证据理论进行结合的的风险评估方法。首先,根据信息安全风险评估的流程和要素,建立风险评估指标体系,确定风险影响因素;其次,通过高斯隶属度函数,求出专家对各影响因素的评价意见隶属于各个不同评价等级的程度;再次,将其作为DS理论所需的基本概率分配,引入基于矩阵分析和权值分配的融合算法综合多位专家的评价意见;最后,结合贝叶斯网络模型的推理算法,得出被测信息系统所面临的风险大小,并对其进行分析。结果显示,将模糊集理论和DS证据理论应用到传统贝叶斯网络风险评估的方法,在一定程度上能够提高评估结果的客观性。     

Fuzzy risk assessment of mortality after coronary surgery using combination of adaptive neuro‐fuzzy inference system and K‐means clustering

In this paper, a fuzzy expert system based on adaptive neuro‐fuzzy inference system (ANFIS) is introduced to assess the mortality after coronary bypass surgery. In preprocessing phase, the attributes were reduced using a univariant analysis in order to make the classifier system more effective. Prognostic factors with a p‐value of less than 0.05 in chi‐square or t‐student analysis were given to inputs ANFIS classifier. The correct diagnosis performance of the proposed fuzzy system was calculated in 824 samples. To demonstrate the usefulness of the proposed system, the study compared the performance of fuzzy system based on ANFIS method through the binary logistic regression with the same attributes. The experimental results showed that the fuzzy model (accuracy: 96.4%; sensitivity: 66.6%; specificity: 97.2%; and area under receiver operating characteristic curve: 0.82) consistently outperformed the logistic regression (accuracy: 89.4%; sensitivity: 47.6%; specificity: 89.4%; and area under receiver operating characteristic curve: 0.62). The obtained classification accuracy of fuzzy expert system was very promising with regard to the traditional statistical methods to predict mortality after coronary bypass surgery such as binary logistic regression model.     

基于犹豫模糊语言的多阶段多属性决策方法

针对不确定语言条件下的决策问题,考虑专家偏好的阶段性差异,提出基于犹豫模糊语言的多阶段多属性决策方法。首先为了更准确地表达专家在决策过程中的犹豫性,采用犹豫模糊语言来表达专家的评估信息;其次考虑阶段权重的波动性,运用基于专家阶段性偏好的信息熵方法构建阶段权重优化模型确定阶段权重;然后利用最大化偏差法来求解属性权重,并采用基于平均解距离评价(EDAS)方法对备选方案进行排序;最后以某企业选取物流商问题为例,验证该方法的有效性和可行性。     

基于模糊一致矩阵的认知权重综合确定法

从教育专家根据经验量比得出的认知能力权重值中提取一致性信息，并对此进行综合处理，量化了十标度法。在此基础上构造模糊一致矩阵，提出了一种确定认知能力权重的新方法，并进行了算例分析。分析结果表明，求出的认知能力权值排序结果与教育专家根据经验量比得出的权重排序结果完全一致。     

考虑个体累积共识贡献的犹豫模糊语言自适应共识模型

针对犹豫模糊语言信息下的多属性群决策问题,提出一种基于个体累积共识贡献的自适应共识决策模型.首先,利用犹豫模糊语言得分函数,基于经典的信息熵和相对熵理论,综合考虑同一属性下不同方案间的信息差异,以及各方案分别与正理想方案和负理想方案的信息差异,构建确定属性权重的优化模型;然后,提出个体累积共识贡献测度和全局共识测度,利用全局共识度进行共识控制,依据个体累积共识贡献度对专家权重进行自适应修正,构建一种新的犹豫模糊语言自适应共识过程.该过程的特点是对拥有较少合作的非全共识专家执行专家权重惩罚,而且专家权重的更新引起属性权重的自适应更新,反过来又影响个体共识贡献的累积.最后通过一个应急医疗设施选址的共识决策例子表明方法的可行性和有效性.     

A Forex trading expert system based on a new approach to the rule-base evidential reasoning

Currently FOREX (foreign exchange market) is the largest financial market over the world. Usually the Forex market analysis is based on the Forex time series prediction. Nevertheless, trading expert systems based on such predictions do not usually provide satisfactory results. On the other hand, stock trading expert systems called also “mechanical trading systems”, which are based on the technical analysis, are very popular and may provide good profits. Therefore, in this paper we propose a Forex trading expert system based on some new technical analysis indicators and a new approach to the rule-base evidential reasoning (RBER) (the synthesis of fuzzy logic and the Dempster–Shafer theory of evidence). We have found that the traditional fuzzy logic rules lose an important information, when dealing with the intersecting fuzzy classes, e.g., such as Low and Medium and we have shown that this property may lead to the controversial results in practice. In the framework of the proposed in the current paper new approach, an information of the values of all membership functions representing the intersecting (competing) fuzzy classes is preserved and used in the fuzzy logic rules. The advantages of the proposed approach are demonstrated using the developed expert system optimized and tested on the real data from the Forex market for the four currency pairs and the time frames 15 m, 30 m, 1 h and 4 h.