(Example)
LIST OF SYMBOLS

E Three-dimensional Euclidean Space
R A closed and bounded region in E
R Interior of the region P
R Boundary of the region R
Rs, s=1,2,...,S Complementary regular subsurfaces of the boundary aR, s being
a positive scalar
R Finite-element model of the region R
R Finite-element model of the boundary aR
Rs, s=1,2,..S Finite-element models of the complementary
regular subsurfaces aRs, s=1,2,...S
x=(x1,x2,x3) A point in R having coordinates x1, x2,
and x3 with respect to an orthogonal coordinate system
x=(x,y,z) A point in R having coordinates x,y and z with respect to a
Cartesian coordinate system
p Unit outward normal of the boundary aR at a point x e aR
zo Thickness of half thickness
s Optical distance
so Optical thickness or optical half thickness

*First Latin, then Greek letters, both in alphabetical order.