(R1509) TOPSIS and VIKOR Methods for Spherical Fuzzy Soft Set Aggregating Operator Framework

The Spherical Fuzzy Soft (SFS) set is a generalization of the Pythagorean fuzzy soft set and the intuitionistic fuzzy soft set. We introduce the concept of aggregating SFS decision matrices based on aggregated operations. The techniques for order of preference by similarity to ideal solution (TOPSIS) and viekriterijumsko kompromisno rangiranje (VIKOR) for the SFS approaches are the strong points of multi criteria group decision making (MCGDM), which is various extensions of fuzzy soft sets. We define a score function based on aggregating TOPSIS and VIKOR methods to the SFS-positive and SFS-negative ideal solutions. The TOPSIS and VIKOR methods provide decision-making weights. To find the optimal alternative under this condition, closeness is introduced. Also, we obtain an algorithm that deals with the MCGDM problems based on an aggregating operator. Finally, a numerical example of the MCGDM problem is given to verify the practicality of the aggregating operators

Decision Rules for Supplier Selection Using Intuitionistic Fuzzy TOPSIS

This paper provides a methodology for addressing contradiction in the ranking of suppliers when more than one metric functions are adopted in intuitionistic fuzzy TOPSIS (Technique for Order Preference by Similarity to the Ideal Solution) for supplier selection. Our literature search revealed contradictions when more than one metric functions are adopted in the method.  Two types of contradictions were addressed: (i) contradiction of the best supplier, and (ii) contradiction at the middle of the park.  Decision rules algorithms were developed to address the problems.Worked examples were given to illustrate the rules for resolving the contradiction. A major thrust of this paper is the adoption of odd number of metric functions with the use of the ballot strategy. This paper use three metric functions which are Spherical, Euclidean and Hamming metric fuctions. In case of contradiction, the alternatve that gives majority of same rank with respect to the metrics fuctions  is selected.Keywords: Supplier Selection; Intuitionistic fuzzy TOPSIS; Metric Functions; Contraditions; contradiction of best alternatives; contradiction at the middle of the park

An evaluation of E7 countries' sustainable energy investments: A decision-making approach with spherical fuzzy sets

The purpose of this study is to identify important strategies to increase sustainable energy investments in emerging economies. For this situation, first, four different indicators are selected according to the dimensions of the balanced scorecard technique. The weights of these items are computed by using Quantum Spherical fuzzy DEMATEL. In the second phase, emerging seven (E7) countries are ranked regarding the performance of sustainable energy investments. In this process, Quantum Spherical fuzzy TOPSIS is taken into consideration. The main contribution of this study is that prior factors can be defined for emerging economies to increase sustainable energy investments in a more effective way. Furthermore, a novel decision-making model is developed while integrating TOPSIS and DEMATEL with Quantum theory, Spherical fuzzy sets, facial expressions of the experts, and collaborative filtering. It is concluded that competition is the most significant factor for the performance of sustainable energy investments. In addition, the ranking results denote that China and Russia are the most successful emerging economies with respect to sustainable energy investments. It is strongly recommended that emerging countries should mainly consider benchmarking the capacity of energy hubs with the aim of increasing the capacity of ongoing energy plants

Assessing the electricity production capacities of emerging markets for the sustainable investments

It is essential to supply the necessary electricity for both the increase in the quality of life of the citizens and the stable growth of the country’s economy. For countries to have energy independence, they need to increase their electricity generation capacity. However, all alternatives required to increase electrical capacity have both advantages and disadvantages. Within this scope, it is not easy for countries to make the right investment decisions. Therefore, a comprehensive analysis is needed to determine the right investment policy. The purpose of this study is to evaluate the electricity production capacities of emerging markets. A new fuzzy decision-making model has been constructed to find a solution for this situation. The groups for the electricity production capacities are examined by the extension of DEMATEL with Quantum Spherical fuzzy sets and golden ratio. In the following stage, emerging seven economies are ranked by using QSF TOPSIS technique. This situation helps to understand which of these countries are more successful in generating electricity capacity effectively. The main novelty is to define the most significant electricity generation alternatives by a novel model that integrates DEMATEL and TOPSIS with QSFSs and golden ratio. The results demonstrate that solar photovoltaic is the most optimal way to increase electricity capacity of the countries. Additionally, China is the most successful emerging country to generate electricity in an efficient way. Countries should take some actions to increase their solar energy investments. First, it would be appropriate to provide tax exemptions to solar energy investors so that the costs of these projects can be decreased. Additionally, investments in solar energy technologies need to be further increased

Analysis of environmental impact for material production investments using a novel soft computing methodology

The purpose of this study is to evaluate the environmental impacts of material production investments. The factors of Higg Materials Sustainability Index are defined as the parameters. These factors are weighted by considering T-SF TOPSIS-DEMATEL. Moreover, the items of the life cycle process are defined as alternative set for measuring the environmental effects of each process in the sustainable production investments. These alternatives are ranked with interval valued SF MAIRCA. The calculations are also made for different t, u and d values with the aim of making comparative evaluations. The main contribution of this study is that a priority analysis has been made so that the most significant indicators are defined for the companies to increase sustainability in material production investment process. Another important novelty of this paper is that a new model is created by the name of TOPSIS-DEMATEL. This situation has a positive influence on both increasing methodological originality and overcoming criticized issues of DEMATEL. The results are quite similar for all conditions, so it is understood that the proposed model provides consistent and coherent findings. It is concluded that chemistry is the most critical factor for environmental impact for material production investments. Moreover, recycle is determined as the most optimal alternative

Novel possibility spherical fuzzy soft set model and its application for a decision making

We talk about possibility spherical fuzzy soft set (shortly PSFS set) has much stronger ability than possibility Pythagorean fuzzy soft set (shortly PPFS set) and intuitionistic fuzzy soft set. The PSFS soft set is a generalization of PPFS set and soft set. Here we talk through some operations consisting of complement, union, intersection, AND and OR. We verify that the De Morgan’s laws, associate laws and distributive laws are satisfied in the case of PSFS sets. Also we discuss comparative analysis for the soft set model under the scheme of PSFS sets. Finally, an illustrative example is mentioned for the soft set model using PSFS set.Publisher's Versio

Using quantum spherical fuzzy decision support system as a novel sustainability index approach for analyzing industries listed in the stock exchange

This study aims to identify critical factors of the sustainability index (SI) and evaluate the industries listed in the stock exchange based on the performance of this index. For this purpose, a new fuzzy decision-making model has been created. Firstly, 12 different criteria for the SI are weighted by decision using trial and evaluation laboratory (DEMATEL) methodology based on quantum spherical fuzzy sets (QFS) with golden cut. Secondly, SI performances of the 10 industry alternatives are ranked by extended technique for order of preference: according to similarity through an ideal solution (TOPSIS) with QFS. The main novelty of this study is to identify significant sustainability criteria for the companies to join this index with an original fuzzy decision-making methodology. For this purpose, the analysis results help the companies to act without incurring extreme costs. It is determined that the usage of renewable energy has a significant impact on all other criteria, and while using clean energy, the companies get a chance to improve other criteria of SI. Additionally, based on the weighting results, the use of renewable energy is the most critical criterion to be included in SI. Similarly, recovery of the resources also has a significant contribution. Finally, the ranking results indicate that communication and IT is the most successful industry for SI. Hence, it would be appropriate for businesses to attach importance to the use of renewable energy. In this way, the carbon emission problem would be minimized, and the image of businesses will rise in the eyes of both consumers and investors. In this framework, companies can join microgrid energy management systems to handle high-cost problems of renewable energy investment projects. Owing to microgrid energy applications, the costs of using renewable energy can be shared with other companies, and since this situation can reduce the cost per unit, it will be possible to increase the use of renewable energy.Istanbul Medipol Universit

Trapezoidal Spherical Fuzzy Numbers and its Application to Fuzzy Risk Analysis

Spherical fuzzy sets are a broader type of fuzzy sets that have the ability to handle various scenarios using their membership, non-membership, and neutral membership grades. These sets require that the total of the squares of these grades be no greater than one. This condition extends the possible values for the three grades and enables decision makers to have a wider range of options when assessing a situation. In solving real life problems, it is necessary to describe a real number as a spherical fuzzy set to incorporate the fuzziness, thus, the need to use trapezoidal spherical fuzzy numbers (TSFN).  In this paper, the membership functions of the TSFN, their arithmetic operations and their properties are discussed. Also, a ranking function is proposed to order the TSFNs. All these are used to solve a fuzzy risk analysis problem whose parameters are presented as TSFNs

Digital transformation in the defense industry: A maturity model combining SF-AHP and SF-TODIM approaches

As an inevitable process, digitalization has become a priority for many companies. The measurement of digital maturity is the first step toward adequately executing this. Although digital maturity models (DMM) have been developed for different sectors in the literature, such studies in the defense industry are lacking due to sector-specific dynamics. This study aims to close this gap and proposes a digital maturity model specific to the defense industry. In this study, a novel model was developed that combines the SF-AHP and SF-TODIM methods due to the uncertainty and hesitancy contained in the evaluation. The validity of the presented novel model has been demonstrated in a prominent defense company in Turkey. According to the results, the most notable digital maturity dimensions are the evaluation of opportunities and alignment with stakeholders. In addition, the model indicates that the company owns the required soft skills, such as leadership, organizational culture, and strategic determination for digital transformation (DT). On the other hand, essential hard skills such as technology and operational competencies are yet to be improved. Lastly, sensitivity and comparison analyses are conducted to validate and verify the obtained results’ stability and robustness

Multiple-Criteria Decision Making

Decision-making on real-world problems, including individual process decisions, requires an appropriate and reliable decision support system. Fuzzy set theory, rough set theory, and neutrosophic set theory, which are MCDM techniques, are useful for modeling complex decision-making problems with imprecise, ambiguous, or vague data.This Special Issue, “Multiple Criteria Decision Making”, aims to incorporate recent developments in the area of the multi-criteria decision-making field. Topics include, but are not limited to:- MCDM optimization in engineering;- Environmental sustainability in engineering processes;- Multi-criteria production and logistics process planning;- New trends in multi-criteria evaluation of sustainable processes;- Multi-criteria decision making in strategic management based on sustainable criteria