Mappings Semigroups in Uniformly Convex Banach Spaces

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We should note here that ru(A) taken as a function of u defined on a bounded ... structure. It is already known that uniformly convex Banach spaces have uni-.
             

     (α)                 

                

    !    " #$ %        &  '   !

               " #!

                   ' (  ) & )  )  (α)'  *   *  + 

 $     *  ! ,$        * *   (α)'   *   *   ) *              

   ! "$  % !!& ' -./0 ()*!'      1     1 (α)'  *1 ,$  1 k '2 + 1     1     $ ! 

          



0   2 X   #      $ ,  C   C       $    X  !  T : C −→ C      (α)'  *      )      a   b   a + 2b = 1     3004 T x − T y ≤ a x − y + b T x − y + T y − x , ∀x, y ∈ C. 5     * )        607 ! )  

 $     *   (α)'  *    8  & b = 0  3004           )   ) * $ 9 5&   T : [0, 1] −→ [0, 1]     * *   0  x = 1 T (x) =  x = 1 (   8         $       

   R     (α)'  * ( 8  &  a=b= . :       * T (t) : t ∈ R     C  X        * *      C ' *         ) *   9 34 T (0) = I  )  I      *    X  34 T (s + t) = T (s)T (t)   s, t ∈ R  34 lim T (t)x − x = 0   x ∈ C     607  )  ) *   9 +   607  H      C       T

T

T

T

T

T

T

1 2

+

1 3

0

+

t→0+

      H   T    (α)  C         x0 ∈ C       T i x0 : i ∈ N        x ∈ C      1 i T x, n i=1 n−1

Sn (x) =

       T  C 

607





 Γ = T (t) : t ∈ R+   C0    (α)                H  !

       a  b         t  

         x0 ∈ C    T (t)x0 : t ∈ R+        x ∈ C      +  

1 St (x) = t



0

t

T (τ )x0 dτ,

   H       Γ

     



!            *           )    *      ,$      * 6;7 6         9

>    K  X  )    diam(K)    sup x − y : x, y ∈ K .

5        u ∈ A ) 

r(A) ≤ ru (A) ≤ diam(A).

?      r (A) &      u ,           $   A  X   r : A −→ R     '     $    )  C(A)       $ !   u ∈ A       r (A) = diam(A)   u       (             $  A                     !    $   K   #   X              $   H  K   diam(H) > 0            ! #   X                $    X       5      8    #   X    9 r(K) N(X) = sup : K ⊂ X       $ diam(K) > 0 . diam(K)   N(X) ≤ 1   N(X) < 1       X          (    & )      $ #     '        √   ) & )  /         8  =  2 ! *      N(X)   & )   8    & )   u

u

u

          



  )       

 )            $   X          δ (1) > 0 !  )     = 1 3;04 λ δ (1 − )N(X) = 1. λ      =  λ > 1 2  )  G           R      * N )  x ∈ X   x     X            x    x 3;;4 r(x, {x }) = lim sup x − x. > x  ,$ 3;;4 ,   

*       $    x   X   R  )  K                 {x }  K      X

2 −1 X

−1

+

u u∈G

u u∈G

u

u u∈G

u→+∞

u

+

u u∈G

5

r(K, {xu }) = inf r(x, {xu }) : x ∈ K .   xu     K       A(K, xu ) = x ∈ K : r(x, xu ) = r(K, xu ) .   X A(K, xu )   X A(K, xu )



   

(  & )    @$              $          $     *      K  X  ) )  co(K)      $   K    co(K) = ∩{H : H  $   K ⊂ H} )    *    ) )   ) *  ,   67 !

   X      "       {xt }t∈G    X      y ∈ co({xt : t ∈ G})   

3