Материал: 1458
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y(t), -
x(t).
x(t ) xmax sin t; |
(2.54) |
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y (t ) ymax sin( t ), |
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xmax, ymax – , – |
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– .
( ) – -
A = ymax/xmax ( . 2.10, ).
( ) –
. 2.10, ).
( ) –
, [+1; j]
( . 2.10, ), -
. -
Ai , i .
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. 2.10. :) ; ) ; )
–
, ( . 2.11).
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L,
20lgK
lg
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0 |
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lg
. 2.11.
– L = f(lg ), – = f(lg ).
L lg :
lg b , 10b ; |
(2.55) |
L 20 lg A . |
(2.56) |
L [ ].
– , -
.
1 = 10 – 10 . 2 = 20 – 100 ;
3 = 30 – 1000 .
lg [ ].
– ,
10 .
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– , -
( ).
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:
L = 20lgK lg = 0 ( = 1) – ,
K – ;
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0 – ,
;
– – L ;
[ ].
2.10.
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, . .
Y(p) X(p)
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W ( p) |
Y ( p) |
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(2.57) |
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X ( p) |
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B( p) |
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b p m b p m 1 |
b p m 2 |
... b |
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W ( p) |
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1 |
2 |
m |
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(2.58) |
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a0 p n a1 p n 1 |
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A( p) |
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a2 p n 2 ... an |
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B(p) = b0 pm + b1 pm-1 + b2 pm-2 + … + bm – ,(p) = a0 pn + a1 pn-1 + a2 pn-2 + … + an – .
,
n. (2.57) , -
Y(p) = W(p X(p). |
(2.59) |
X -F ( . 2.1) ( )
:
F(p) = 0, A( p) Y ( p) B( p) X ( p) ;
X(p) = 0, A( p) Y ( p) Q( p) F ( p) .
, , -
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WX |
( p) |
Y ( p) |
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B( p) |
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(2.60) |
X ( p) |
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A( p) |
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WF |
( p) |
Y ( p) |
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Q( p) |
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(2.61) |
F ( p) |
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A( p) |
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(2.60)
, (2.61) -
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(2.60) (2.61).
2.11.
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. -, .
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x K . K -
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= K· . |
(2.62) |
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(2.63) |
W(p) = K. |
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( . 2.12, ) |
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h(t) =K 1(t). |
(2.64) |
( . 2.12, ) |
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A K ; |
(2.65) |
L 20 lg K ; |
(2.66) |
0 . |
(2.67) |
, [+1; j],
, ( . 2.12, ).
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h(t) |
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K |
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x = 1(t) |
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L, |
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jV( ) |
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20 lg K |
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lg |
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K |
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U( ) |
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lg |
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. 2.12. :) ; ) ; )
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