On the basis of previous scholars’ research, we improve the traditional TOmada de Decisão Interativa e Multicritério (TODIM) along with Cumulative Prospect Theory (CPT) under the 2-tuple linguistic Pythagorean fuzzy sets (2TLPFSs) in this article. First of all, we give some definitions of Pythagorean fuzzy sets, 2TLPFSs, and the 2-tuple linguistic Pythagorean fuzzy weighted average as well as 2-tuple linguistic Pythagorean fuzzy weighted geometric operators. After that, according to the existing researches, we simply introduce the TODIM method and TODIM method under 2TLPFSs. Furthermore, we propose the TODIM method based on CPT (CPT–TODIM) for multiple attribute group decision-making (MAGDM) with 2TLPFSs. Finally, a numerical example about company credit risk assessment is used to explain the new proposed method. Comparing with other methods, there is no doubt that this new method has superiority. To be exact, because the new method fully considers the mental factors of decision makers, it can better solve the uncertainty of MAGDM and improve the rationality of decision-making.

Network security is a very important issue in recent years. For many new or traditional enterprises, utilizing internet to store and analyze data has become an indivisible part of their production and operation. But many enterprises do not have enough ability to ensure the security of information, so the choice of the optimal network security service provider has become a practical problem faced by many ordinary companies. In this paper, we establish bipolar fuzzy interactive multi-criteria decision-making (TODIM) based on the cumulative prospect theory (CPT-TODIM) model for dealing with the problem of multi-attribute group decision making, and this special model is applied to the field of network security about the issue of network security service provider selection. The second and third parts of this paper introduce the knowledge of bipolar fuzzy and the initial CPT-TODIM method. In the fourth part, we discuss the bipolar fuzzy CPT-TODIM model in detail. In the last two parts of this article, the method proposed in this paper is applied to the field of network security provider selection and compared with other methods. The results show that bipolar fuzzy CPT-TODIM method with unique advantages in some aspects is reasonable and effective, and can be applied to more uncertain decision fields. It is hoped that this method can help enterprises make better decisions.

The 2-tuple linguistic neutrosophic set (2TLNS) does a good job in coping with vague and uncertain environments and has been widely used in numerous fields. In this article, we come up with a new solution of multiple attribute group decision-making (MAGDM) problems, named as the modified TODIM method based on cumulative prospect theory and 2-tuple linguistic neutrosophic sets (CPT-2TLN-TODIM method). To ensure relatively objective attribute weights, the CRITIC is integrated into this new model in this paper. The CPT-2TLN-TODIM method fully considers the psychological state of decision makers that makes it more realistic. What's more, we introduce the application of CPT-2TLN-TODIM method in the evaluation of network security assessment team for verifying the practicability of the CPT-2TLN-TODIM method. And finally, the reliability of CPT-2TLN-TODIM method is confirmed by comparing with other existed methods. In the immediate future, we will further explore the application of this method in other fields and keep trying to put forward more scientific and reasonable methods to solve MAGDM problems.

The dual hesitant Pythagorean fuzzy set (DHPFS) consists of two parts, that is, the membership hesitancy function and the nonmembership hesitancy function, supporting a more exemplary and flexible access to assign values for each element in the domain. It is very suitable to handle the situation that there are various possible values in membership and nonmembership degrees to depict the true circumstance. The bidirectional project method of DHPFS calculates method considered not only the bidirectional projection magnitudes and the distance but also includes angle between objects evaluated. Therefore, this paper proposes a bidirectional project method of DHPFS to handle the multiple attribute decision-making (MADM) problem under the dual hesitant Pythagorean fuzzy environment. Through the measure between each alternative decision matrix and the positive and negative ideal alternative matrix, the ranking order all alternatives can be used to select the best alternative. Furthermore, a model for MADM has been given. Finally, a numerical example for performance assessment of new rural construction has been given to demonstrate the application of bidirectional project method of DHPFS, and we used the dual hesitant Pythagorean weighted Bonferroni mean to compare its reasonable and effectiveness.

In this paper, the Hamy mean (HM) operator, weighted HM (WHM), dual HM (DHM) operator, and dual WHM (WDHM) operator under the q-rung orthopair fuzzy sets (q-ROFSs) is studied to propose the q-rung orthopair fuzzy HM (q-ROFHM) operator, q-rung orthopair fuzzy WHM (q-ROFWHM) operator, q-rung orthopair fuzzy DHM (q-ROFDHM) operator, and q-rung orthopair fuzzy weighted DHM (q-ROFWDHM) operator and some of their desirable properties are investigated in detail. Then, we apply these operators to multiple attribute decision-making problems. Finally, a practical example for enterprise resource planning system selection is given to verify the developed approach and to demonstrate its practicality and effectiveness.

In this paper, according to the Maclaurin symmetric mean (MSM) operator, the dual MSM (DMSM) operator and the q-rung interval-valued orthopair fuzzy set (q-RIVOFS), we develop some novel MSM operators under the q-rung interval-valued orthopair fuzzy environment, such as, the q-rung interval-valued orthopair fuzzy MSM operator, the q-rung interval-valued orthopair fuzzy weighted MSM (q-RIVOFWMSM) operator, the q-rung interval-valued orthopair fuzzy DMSM operator, and the q-rung interval-valued orthopair fuzzy weighted DMSM operator. In addition, some precious properties and numerical examples of these new operators are given in detail. These new operators have the advantages of considering the interrelationship of arguments and can deal with multiple attribute group decision-making problems with q-rung interval-valued orthopair fuzzy information. Finally, a reality example for green suppliers selection in green supply chain management is provided to demonstrate the proposed approach and to verify its rationality and scientific.

The Maclaurin symmetric mean (MSM) operator is a classical mean type aggregation operator used in modern information fusion theory, which is suitable to aggregate numerical values. The prominent characteristic of the MSM operator is that it can capture the interrelationship among the multi-input arguments. In this paper, we extend the MSM operator and dual MSM operator to q-rung orthopair fuzzy sets to propose the q-rung orthopair fuzzy MSM operator, q-rung orthopair fuzzy dual MSM operator, q-rung orthopair fuzzy weighted MSM operator, and q-rung orthopair fuzzy weighted dual MSM operator. Then, some desirable properties and special cases of these operators are discussed in detail. Finally, a numerical example is provided to illustrate the feasibility of the proposed methods and deliver the sensitivity analysis and comparative analysis.