Fig 2. Investigated feedback loops.
Blue and red arrows represent, respectively, inputs from and outputs to elements outside the system boundaries. Other colors map to feedback loops under analysis.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.