, , . , () ( ).
, , .
,
- :
(II.1)
, (II.1)
(II.2)
+Rj=0 (II.3),
(II.3) , m. Rj , . , , (II.2) (II.3).
. .
Pt : Rj, RD RS. :
RJ + RD + RS = P(t) (II.4)
:
RS = k x (II.5a)
(II.5)
RD :
(II.5)
(II.4) :
(II.6)
() , () .
. , .
.
13, 14