These labels are orientation labels used in the hatch area to help the astronauts orient themselves when entering a new module. Used thus far in the US Lab and MPLM.

So far as the ideological orientation of value of Sima's father and son is concerned, although it was complicated of their ideas, in general, they two praised highly Huanglao doctrine.

This is very handy for those times when you get too far away and lose orientation.