Internal Doors
On Wed, 23 Feb 2022 08:59:43 +0000
Spike snipped-for-privacy@mail.I had to look up rugosity:
Rugosity, f?, is a measure of small-scale variations of amplitude in
the height of a surface, {displaystyle f_{ ext{r}}
=A_{ ext{r}}/A_{ ext{g}}} where A?