Usually, an identification of an open system in a world means a process of specifying its border, resolving it into components, and extracting a regularity of its time evolution with input from the environment. This process formally corresponds to the extraction of simulation relation. In the real world, however, the simulation relation suffers ceaseless collapse and resets. In this study, I clarify this situation, and propose a new framework for extracting systems, which positively exploit the collapse of (a modified) simulation relation. Some features of the proposed framework are reviewed.