+ + − + + = δ + δ

=−=

( )= − ( )( )= − −

= =

= =

=

( ) ( )( )− + − + − −=

−

=

= =

λ

Φ

Φ

π π π

( )λ Φ

Φ

−

λ

Σ

( )Φ = − Σ

λ

λ

Φ

− −

Φ −

( )= + +

π λ

λ

( ) =

( ) =

( ) = ( ) =

( )−

( )−

Φ

( )Φ = −

= =

+

+λ

λ

ρ

η

Δ = − >

( )Δ= −

η

Δ =

= =−=

−= = =

=− −=

=

( )

⎯⎯→←⎯⎯( )

=−

Λ= − Λ

Δ

Δ

Δ

Δ

( )−

= + = + α

+

( ) α

( )Δ = −

=

= = −= =

Δ

ε=

( )=

Δ = −

( )Δ = α −− Δ = α

= = − −ε = − −α =

Δ

−Δ =

≈

ϕ

ϕ

ρ

ρ

•• −=

•• − −=

•• −η =

•• −=

=

( )− ( )−

=

( )− ( )−

( )−

IM

PR

IM

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