广义毕达哥拉斯模糊集成算子及其决策应用

研究毕达哥拉斯模糊决策环境下的集成算子及其决策应用.给出拟加权几何集成算子和拟有序加权几何算子的概念, 并分析 它们的性质.将有序加权平均算子、有序加权几何算子、拟有序加权平均算子和拟有序加权几何算子推广到毕达哥拉斯 模糊决策环境, 定义毕达哥拉斯模糊有序加权平均算子、广义毕达哥拉斯模糊有序加权平均算子、毕达哥拉斯模糊有序加权几何算子、广义毕达哥拉斯模糊有序加权几何 算子、拟毕达哥拉斯模糊有序加权平均算子和拟毕达哥拉斯模糊有序加权几何算子.提出基于广义毕达哥拉斯模糊集成算子的决策方法, 并通过实例验证其可行性.     

直觉模糊相似关系的构造方法

传统的模糊相似关系构造方法已不能用于直觉模糊相似关系的构造。基于直觉模糊集的相异度和相似度,研究了直觉模糊相似关系的构造问题。对几种现有直觉模糊集相似度与相异度度量方法进行了分析,在此基础上定义了直觉模糊集的相异度,并给出一种有效的直觉模糊集相异度和相似度度量方法,提出一种实用的直觉模糊相似关系构造方法,以具体算例验证和表明了方法的正确性和有效性。     

融合PFS与RS的案例知识供需匹配研究

面对日益丰富的知识资源,对知识供需匹配问题的研究有助于知识资源的有效配置、解决用户“知识迷向”问题,实现知识资源价值最大化,具有重要的理论意义和实践价值。将毕达哥拉斯模糊集（PFS）与模糊粗糙集相结合,建立毕达哥拉斯模糊粗糙集（PFRS）模型,用以处理模糊不确定性知识资源的知识供需匹配问题;通过引入PFS相关测度对属性相似度进行改进,并基于知识属性权重求出用户需求与案例知识之间的视图相似度,确定匹配结果。实证分析验证了所提方法的合理性与可行性,与既有方法相比,通过引入毕达哥拉斯模糊集,对模糊知识的描述更加客观,具备一定的理论优势;同时,用加权相关系数表示视图相似度,使匹配结果更加准确,提高了匹配精度。     

直觉模糊集的聚类方法研究

对基于直觉模糊集的聚类问题进行了研究．首先给出直觉模糊相似度的概念，并构建了直觉模糊相似矩阵和直觉模糊等价矩阵；然后定义了直觉模糊相似矩阵的合成运算法则．给出直觉模糊相似矩阵转化为直觉模糊等价矩阵的途径；此外．还分别定义了直觉模糊相似矩阵和直觉模糊等价矩阵的λ-截矩阵，进而给出了直觉模糊集的一种聚类方法；最后通过算例对该方法进行了说明和分析．     

一种新的直觉模糊相似矩阵构造方法

基于直觉模糊相似度和相异度,研究了直觉模糊相似矩阵构造问题。给出了直觉模糊相似度和相异度的标准定义,选取了有效的直觉模糊相似度量和相异度量方法;在分析了现有的几种直觉模糊相似矩阵构造方法基础上,提出了一种新的直觉模糊相似矩阵构造方法。通过算例分析,验证了方法的有效性。     

毕达哥拉斯犹豫模糊集成算子及其决策应用

针对毕达哥拉斯犹豫模糊多属性决策中,集成算子的重要作用以及集成算子不完善的情况,较为系统地研究了毕达哥拉斯犹豫模糊集成算子。为此,在毕达哥拉斯模糊数的运算和运算法则基础上,定义了毕达哥拉斯犹豫模糊有序加权平均算子（PHFOWA）、广义有序加权平均算子（GPHFOWA）和混合平均算子（PHFHA）,以及毕达哥拉斯犹豫模糊有序加权几何平均算子（PHFOWG）、广义有序加权几何平均算子（GPHFOWG）和混合几何平均算子（PHFHG）,并结合数学归纳法,分别给出了它们的计算公式,讨论了它们的有界性、单调性和置换不变性等性质。建立了基于毕达哥拉斯犹豫模糊集成算子的多属性决策方法,并应用算例和相关方法比较说明了决策方法的可行性与有效性。     

毕达哥拉斯模糊优先集成算子及其决策应用

作为直觉模糊集的推广形式,毕达哥拉斯模糊数能更好地刻画现实中的不确定性,此外在某些问题上,方案的属性之间往往具有优先关系,针对此类信息的集成问题,将毕达哥拉斯模糊数与优先集成算子相结合,提出了毕达哥拉斯模糊优先集成算子,包括毕达哥拉斯模糊优先加权平均算子和毕达哥拉斯模糊优先加权几何算子,并讨论了这些算子的性质。在此基础上,提出了毕达哥拉斯模糊优先集成算子的多属性决策方法,最后将其应用于国内四家航空公司服务质量评价中,说明了该算子的有效性和可行性。     

基于毕达哥拉斯模糊幂加权平均算子的多属性群决策方法

研究了毕达哥拉斯模糊环境下的多属性群决策问题。首先,将毕达哥拉斯模糊信息引入幂平均加权算子,提出毕达哥拉斯模糊幂加权平均（PFPWA） 算子,并研究所提算子的基本性质。然后,在毕达哥拉斯模糊数（PFN） 为信息输入的框架内,提出基于毕达哥拉斯模糊幂加权平均算子的群决策方法。所提出的方法使用毕达哥斯拉信息使得决策者的信息表达更加灵活,并且在信息集结过程中采用幂加权平均算子能够同时考虑专家权威与评估信息的可信度。最后,通过案例分析验证了所提方法的可行性和有效性。     

乘型一致性毕达哥拉斯模糊偏好关系

毕达哥拉斯模糊偏好关系(PFPR)是直觉模糊偏好关系的推广,也是毕达哥拉斯模糊集的重要研究领域.相对于其他模糊偏好关系而言,毕达哥拉斯模糊偏好关系在表达决策者的模糊偏好时更加灵活有力.在乘型一致性区间模糊偏好关系和乘型一致性直觉模糊偏好关系研究成果的启发下,定义毕达哥拉斯模糊偏好关系的乘型一致性,并提出利用毕达哥拉斯模糊权重向量构造乘型一致性毕达哥拉斯模糊偏好关系的公式.以给定的毕达哥拉斯模糊偏好关系与构造的乘型一致性毕达哥拉斯模糊偏好关系的偏差最小为目标函数建立并求解优化模型,从而获取毕达哥拉斯模糊偏好关系的标准化权重向量,为方案排序提供一种可行的方法.计算实例分析表明,所提出方法是可行有效的.     

毕达哥拉斯犹豫模糊集的相关测度

毕达哥拉斯犹豫模糊集,既能描述隶属度与非隶属度之和超过1、而平方和不超过1的模糊现象,又能表达决策者在隶属度和非隶属度上的犹豫不决,因此它是表达不确定现象的一个强有力工具.考虑到相关测度在统计学和管理科学中发挥着重要的作用,在模糊集、直觉模糊集以及毕达哥拉斯模糊集等相关测度基础上,研究毕达哥拉斯犹豫模糊集的相关测度.为此,定义毕达哥拉斯犹豫模糊集的信息能量、相关指标以及相关系数,证明相关系数的性质.由于决策中经常要考虑到属性权重,定义毕达哥拉斯犹豫模糊集的加权相关系数,并讨论其性质.最后,通过求出每个方案与正理想方案之间的加权相关系数,实现方案的排序择优,并通过算例表明其可行性与有效性.     

Distance and similarity measures of Pythagorean fuzzy sets and their applications to multiple criteria group decision making

The main feature of Pythagorean fuzzy sets is that it is characterized by five parameters, namely membership degree, nonmembership degree, hesitancy degree, strength of commitment about membership, and direction of commitment. In this paper, we first investigate four existing comparison methods for ranking Pythagorean fuzzy sets and point out by examples that the method proposed by Yager, which considers the influence fully of the five parameters, is more efficient than the other ones. Later, we propose a variety of distance measures for Pythagorean fuzzy sets and Pythagorean fuzzy numbers, which take into account the five parameters of Pythagorean fuzzy sets. Based on the proposed distance measures, we present some similarity measures of Pythagorean fuzzy sets. Furthermore, a multiple criteria Pythagorean fuzzy group decision‐making approach is proposed. Finally, a numerical example is provided to illustrate the validity and applicability of the presented group decision‐making method.     

基于信息测度的勾股模糊决策模型及其应用

相对于直觉模糊集，勾股模糊集能够更为全面和有效地表达描述复杂问题中的不确定和非一致信息，使其受到了广泛研究。对于属性评价值为勾股模糊数并且属性指标权重信息数据完全未知的多属性决策问题，以提出的勾股模糊信息测度为基础，设计了新的多属性决策模型。该模型运用对数函数设计了一种新的勾股模糊数信息熵计算方法；引入了勾股模糊相似度概念，并结合对数行数提出勾股模糊数相似度的衡量方法，随后挖掘出勾股模糊数的信息熵和相似度之间的内在联系；运用提出的勾股模糊熵和相似度计算方法，构建新的多属性决策模型，并进行应用研究。实验结果表明，提出的模型合理有效，同时拓展了模型的使用范围。     

On generalized similarity measures for Pythagorean fuzzy sets and their applications to multiple attribute decision-making

In this paper, we develop a new and flexible method for Pythagorean fuzzy decision-making using some trigonometric similarity measures. We first introduce two new generalized similarity measures between Pythagorean fuzzy sets based on cosine and cotangent functions and prove their validity. These similarity measures include some well-known Pythagorean fuzzy similarity measures as their particular and limiting cases. The measures are demonstrated to satisfy some very elegant properties which prepare the ground for applications in different areas. Further, the work defines a generalized hybrid trigonometric Pythagorean fuzzy similarity measure and discuss its properties with particular cases. Then, based on the generalized hybrid trigonometric Pythagorean fuzzy similarity measure, a method for dealing with multiple attribute decision-making problems under Pythagorean fuzzy environment is developed. Finally, a numerical example is given to demonstrate the flexibility and effectiveness of the developed approach in solving real-life problems.     

Pythagorean fuzzy multicriteria group decision making through similarity measure based on point operators

In this paper, a series of similarity measures based on point operators for Pythagorean fuzzy sets are proposed. Using the proposed similarity measures, two new aggregation operators, viz., Pythagorean fuzzy‐dependent averaging operator and Pythagorean fuzzy‐dependent geometric operator, are developed. The advantage of using these operators is that the influence of unfair arguments of aggregated results could be eliminated, since the associated weights are taken from the aggregated Pythagorean fuzzy arguments. Also, the proposed operators have the capability to adjust the degree of aggregated arguments with the controlling parameters. To establish the application potentiality of those operators, a methodology for solving multicriteria group decision‐making problems having Pythagorean fuzzy arguments is developed. A numerical example is provided to demonstrate the proficiency of the proposed method. The achieved results are compared with the results of other existing technique.     

A ranking function based on principal‐value Pythagorean fuzzy set in multicriteria decision making

Multicriteria decision making (MCDM) has been attracting attention in recent years. There are two essential directions in the research territory, one direction is the research of representation of evaluation information and another is the construction of ranking function. In this paper, we consider some nonstandard fuzzy sets, intuitionistic, and interval‐valued fuzzy sets. Especially, the Pythagorean membership grade and Pythagorean fuzzy set receive much attention. Then, to reflect the importance of principal value, we shall propose the principal‐value Pythagorean fuzzy number (p‐PFN) and principal‐value Pythagorean fuzzy set. Furthermore, a novel ranking function is constructed to select the ideal alternative(s) based on p‐PFNs in MCDM. Finally, an investment strategy decision‐making problem is proposed to reveal the availability and practicability of the function under the new environment.     

Linguistic Pythagorean fuzzy sets and its applications in multiattribute decision‐making process

In this article, a new linguistic Pythagorean fuzzy set (LPFS) is presented by combining the concepts of a Pythagorean fuzzy set and linguistic fuzzy set. LPFS is a better way to deal with the uncertain and imprecise information in decision making, which is characterized by linguistic membership and nonmembership degrees. Some of the basic operational laws, score, and accuracy functions are defined to compare the two or more linguistic Pythagorean fuzzy numbers and their properties are investigated in detail. Based on the norm operations, some series of the linguistic Pythagorean weighted averaging and geometric aggregation operators, named as linguistic Pythagorean fuzzy weighted average and geometric, ordered weighted average and geometric with linguistic Pythagorean fuzzy information are proposed. Furthermore, a multiattribute decision‐making method is established based on these operators. Finally, an illustrative example is used to illustrate the applicability and validity of the proposed approach and compare the results with the existing methods to show the effectiveness of it.     

基于一种新得分函数和累积前景理论的毕达哥拉斯模糊TOPSIS法

针对属性权重未知、评价信息为毕达哥拉斯模糊数的多属性决策问题,对毕达哥拉斯模糊集的得分函数进行深入分析,为解决现有得分函数中存在的不足,提出一种新得分函数,通过证明其相关定理,分析新得分函数的性质.将新得分函数运用到毕达哥拉斯模糊多属性决策问题中,以帮助决策者更好地处理模糊的决策信息.此外,针对现有大多数毕达哥拉斯模糊多属性决策方法基于决策者是完全理性的假设,忽略决策者在面临风险时的不同主观价值感受,引入累积前景理论,提出基于新得分函数和累积前景理论的毕达哥拉斯模糊TOPSIS法.该方法利用前景价值代替各方案与正负理想解之间的距离测度,能够避免忽略不同属性间相关性对决策结果造成的影响,同时将各属性的灰靶贡献度近似看作对应指标对评价结果的重要程度以确定各属性的权重大小.最后,通过实例分析验证了所提出得分函数及相关定理的正确性,并通过仿真数据进一步验证了所提出方法的有效性和可行性.     

The interval-valued hesitant Pythagorean fuzzy set and its applications with extended TOPSIS and Choquet integral-based method

The hesitant Pythagorean fuzzy set is frequently considered as a solution for decision making under uncertainty. Whereas the representation of uncertain information might be not sufficient in the hesitant Pythagorean fuzzy environment, thus the concept of interval-valued hesitant Pythagorean fuzzy sets (IVHPFSs) is proposed. Specifically, we first propose the concept of IVHPFSs and then study the operational rules and distance measures of IVHPFSs in detail. To ease the possible application, we explore two decision-making processes in the setting of IVHPFSs by drawing support from the technique for order preference by similarity to ideal solution and Choquet integral-based method. Finally, the selecting processes of project private partner are also presented to demonstrate the decision-making processes based on IVHPFSs and compared with some similar techniques.