Issue 48

A. Fesenko et alii, Frattura ed Integrità Strutturale, 48 (2019) 768-792; DOI: 10.3221/IGF-ESIS.48.70

   , ( , , ) (1 )w ( , , ) Z x y h x y h

             1 ( ) ( ) 2 G x a y b 2

1

 

T x y h

( , , )

.

0

0

In the domain of Fourier’s transforms (the cosine transform with regard to the variable x and full Fourier transform with regard to the variable y ) one can derive two boundary problems. First, it is formulated for the unknown function ( , , ) S x y z

 S z N z  2 ( )

  

 ( ) 0,

 (0) 0

 z h S h  ,

S

( ) 0, 0

S





 ( ) 0 S z , and, hence,

 ( , , ) 0 S x y z .

It’s obvious, that this problem has a trivial solution 

 ( ), w ( ) Z z z the one dimensional boundary problem is stated

For the functions 

 ( ) ( ), 0

 

L z z y f

z h

2

(24)

    ( ) y

    ( ) y

U z

U z

,

γ

γ

0

0 1

1

2 L is the differential operator of second order

here

2

  " ( ) z

 z N z z Py f '( )

 ( ) ( ), 0

 

2 L z

z h

( ) y I y

Qy

0

 N z T T   2 ( ) z

 



1

0

  

     w ( ) ( ) ( ) z Z z z y       

  

1

0

*

 

*

  

 

( ) z

I is unit matrix,

,

,

,

is the unknown vector of

  

Q

    * f

Р

2





N

( )

0

0



transforms. The boundary functionals

 , 0,1

i U i

are written in the corresponding forms



  ( ) z z y I y I y γ  [ ] ( )

U

0

1

2

0



  ( ) z z y Ay By γ  [ ] ( )

U

1

1

1 0 0 0

0 0 0 1

0 1

  

  

2

0 N

0

  

  

  

  

  

  

,

,

,

I

I

A

B

1

2

  1 0

0

  

   

 

0

,

.

γ

γ

)

)

1

1

  (2 G

 

1

a e

cos

(2

0

 i b

 

 T h

( )

0

0

The solution of the problem (24) is searched in the form [37]

βα w ( ) z

 y

  

  

h

 0

     ( , ) ( ) z d G f

 ( ) z Ψ γ Ψ γ ( ) z

( ) z

(25)

βα Z z

0

0

1

1

( )

 ( ), 0,1 i

z i Ψ

 ( , ) z G іs Green matrix function,

where

are the basis matrices.

775

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