equation icon  [ ] [ ( ) ] a 1 2 3 a 1 b a 1 2 a 1 2 a b 3 a e0 = 1- --s a0(t) + O(s ) e0+ - s 1- -sabw a (t) + -s a (t)- -s R 0b0(t)w + O(s ) ea. 2 2 2 2 (226)