We are sorry for not being clear on the answer to the last review. This paper tried to present a concept for the smart city structure to cope with major situations such as COVID-19. Therefore, it was not possible to present a specific method of adding or removing a smart city system. Currently, smart city services in Korea are trying to implement a structure that adds and deletes when necessary, as in this paper (Reference #73). However, we apologize for not being able to give you a clear answer on this question. After observing the process of implementing the system, we will present a specific method in the thesis we plan to proceed later.
I would thus include it in Section 2 instead.