- 3


: Ҡ = S i

i =1

T

:

M

= Nm;

M = 1/( Nm) c;

Nn

E (Tp) = S (1/ ic) ,

i =1

Nn

Var (Tp) = S 1/( ic) 2

i

=1

:

R ( t) = exp ( (N m) ct),

t>0 , , .

. , , , . :

m ,

Xi ,

.

Zi (t) i1 im :

Zi ( t) = c (N n i 1), 堠 i = 1 ,..., m; Ti1 < t < Ti ,

m

= S i .

i =1

, .

c N :