Research On Multiple-attribute Group Decision Making Methods With Pythagorean 2-tuple Linguistic Information And Their Applications In Green Supplier Selection

The advent of the industrial age has not only brought about unprecedented development of social economy and production technology,but also a tremendous improvement in material living standards.With it,the environment on which mankind depends for survival has been continuously destroyed,and the resources on the earth have become increasingly scarce.In order to solve environmental problems,all countries in the world are implementing sustainable development strategies.Enterprises have responded to the call to implement green supply chain management.The key link of green supply chain management is to evaluate and select suppliers that meet the requirements of green environmental protection,so it is particularly important to choose right and appropriate methods for evaluating green suppliers.This thesis studies and discusses green supplier evaluation with Pythagorean 2-tuple linguistic information,and conducts a comprehensive and reasonable evaluation of green suppliers based on various evaluation indicators and evaluation methods.This thesis aims to enrich the methodological research in the field of Pythagorean 2-tuple linguistic fuzzy sets and make the selection of green suppliers in green supply chain management more scientifically and reasonably.The main contents and results of this thesis are as follows:(1)On the basis of green supply chain management and green supplier selection theory,according to the principle of index construction,the literature on the fuzzy evaluation index system of green suppliers is summarized,and a set of evaluation index system is constructed.The system is composed of 6 first-level indexes and 19 secondary indicators.(2)Research on the green supplier selection problem in which the attribute value are represented by Pythagorean 2-tuple linguistic fuzzy numbers,the expert weight and the attribute weight are given in advance,and the EDAS group decision model based on the Pythagorean 2-tuple linguistic fuzzy set is proposed.(3)Research on the green supplier selection problem that the attribute values are represented by Pythagorean 2-tuple linguistic fuzzy numbers with completely unknown expert weight,and the attribute weights are given in advance by the decision makers.The objective expert weight is determined based on the measurement of similarity.The CODAS group decision model based on Pythagorean 2-tuple linguistic fuzzy set is proposed.(4)Research on the green supplier selection problem that the attribute values are represented by Pythagorean 2-tuple linguistic fuzzy numbers with completely unknown attribute weight.The CRITIC method is used to obtain the objective weight of the attribute according to the attribute evaluation value given by the expert.A QUALIFLEX group decision model based on Pythagorean 2-tuple linguistic fuzzy set is proposed.