二输运问题 f(x,1)() n(x,0)=g(x) (8) 记x=(,) f(r, t e o dx=flo, t) 0(x)d=o() +a2o2=f(o,t)(9) i(o,0)=() 0)二.输运问题 1. u(x t)e dx u ( t) i x , ~ , w w ò ¥ -¥ - 记 = ( ) ( ) ò ¥ -¥ - f x t e dx = f t i x , ~ , w w 则 ( ) ( ) ò ¥ -¥ - j = j w w ~ x e dx i x ( ) ( ) (10 ) ~ ,0 ~u w = j w ( , ) ( ) 9 ~ ~ ~ 2 2 a u f t dt d u + w = w u (x , 0 ) = j (x ) (8 ) ( , ) (7 ) 2 u a u f x t t - xx =