Solid waste collection system selection for smart cities based on a type-2 fuzzy multi-criteria decision technique

Energy-efficient and eco-friendly information and communication technologies (ICTs) make increasingly significant contributions to daily life while supporting environmental protection and a sustainable economy. Smart city approach aims to integrate ICTs and physical devices to track, analyze, and optimize the parameters of urban operations and services. The purpose of this study is to suggest a type-2 fuzzy multiple criteria methodology to evaluate and rank alternative waste collection systems in a smart city environment. Type-2 fuzzy sets, whose membership functions are also fuzzy, can constitute a strong theoretical base to techniques which can handle problems with vague components. In this regard, type-2 fuzzy TOPSIS method is applied to a real case study from Eskisehir, Turkey. Considering the current needs of Tepebaşı  district, in which there are currently ongoing smart city projects funded by European Union, four alternative concepts are designed. Each of the concepts is based on a particular ICT. Analysis results show that the drone and the visible light communication-based collection systems are the most appropriate systems for the study area. To track the stability of the results to changes in the attribute weights, a sensitivity analysis is also provided. This study can be considered as one of the first attempts to evaluate the integration of emerging ICTs into smart waste collection systems using type-2 fuzzy sets.