equation icon  ( ) ( ) 2 ¨N + 3H - 2d N - 2H + 4H2 + 2d2 - 6Hd - 2d¨ N + k--N ( ) a2 ¨ 2 - dy + 3dR + - 2d - 6Hd + 2d y k2 [ ] = --- dr - 3dp + e-2d(dr- - 3dp -) . (378) 6