Page 123 - IJOCTA-15-1
P. 123

Exponential stability for higher-order impulsive fractional neutral stochastic integro-delay . . .



                       ς
                      Z                                               p−1  p−1  p  −pβ 1 ς   p
                    
                            
 p          M 1 = 6    [3   a e      [E∥φ∥
                                                                                1

                                                                    ¯                                        ¯
            B 5 ≤ E
    T α (ς − ϑ)G(ς, τ, x τ )dw(τ)
                                  p    p−1 ¯       p
                                                                 + L ˜p E∥x ς 1  , x ς 2  , . . . , x ς n ∥ + 2  M g (E∥φ∥ + L ˜p )]]
                      0
                                                                                                     p
                                                                                             p
                                                                              a e
                           ς                                  M 2 = 6 p−1 [2 p−1 p  −pβ 2 ς  [E∥x 1 ∥ + E∥η∥ ]
                         Z                           2  i p                   2
                        h
                    p  ˜     −β 2 (ς−ϑ)            p  p   2
                                                                     p
                                                                                   L].
                ≤ a C p     e         E∥G(ς, τ, x τ )∥  dϑ       + a β  −p CHς pH−1 ˆ
                    2
                                                                     2  2
                         0
                                  ς
                                 Z
                    p  ˜  1− p 2 ¯  −β 2 (ς−ϑ)          p
                ≤ a C p β     L G  e          sup E∥x ϑ ∥ dϑ.
                    2     2                                   By Lemma 5 and equation (10), we have
                                            ϑ∈[0,ς 1 ]
                                 0
                                                                           ˜
                                                                      p
            By Lemma 2 and (H 9 ), we have                    E∥x(ς)∥ ≤ M 1 e −ως ,  ς ≥ −r, ω ∈ (0, σ 1 Λ σ 2 ),
                                                                     ˜

                                                              where M 1 = max M 1 + M 2 , M 3 := 6 p−1 ¯  p
                                                                                                     M g (1 +
                            ς                                   p           p−1 p   1−p   p       p
                           Z                                      ), M 4 := 6  a β                  )], M 5 :=
                                                                                          f
                                                              M σ 1             2   2   [L (1 + M σ 2
                                              H
                  B 6 = E∥   T α (ς − ϑ)σ(ϑ)dB (ϑ)∥ p                     1−  p
                                             Q
                                                                  a C p β
                                                              6 p−1 p 2  ˜  2  2 ¯
                                                                             L G .
                           0
                                         ς
                                        Z                                                  1   1
                         p  −p     pH−1           p           For p ≥ 2 and 1 < q ≤ 2 with  p  +  q  = 1, we have
                     ≤ a β    CHς          E∥σ(ϑ)∥ dϑ
                         2  2                                 the following estimations:
                                        0
                         p  −p     pH−1 ˆ
                     ≤ a β    CHς       L.                                  
  X                    
 p
                         2  2                                               
                 1
                                                                                              k
                                                                                   S α (ς − ς k )I (x ς k
                                                                    B 7 = E
                       )
            From the above estimates together with (9), we                   0<ς k <ς
                                                                             ∞      p
            have                                                           p  X    1  q  X    1 −β1(ς−ς k )    p
                                                                       ≤ a       L           L e         E∥x ς k ∥
                                                                           1       k          k
                                                                              k=1      0<ς k <ς
                             n      p                                       
  X                   
 p
                    p
            E∥x(ς)∥ ≤ 6   p−1  3 p−1  a e −pβ 1 ς  [E∥φ∥ p                  
                 2
                                    1                               B 8 = E
       T α (ς − ς k )I (x ς k  )
                                                                                              k
                        ¯                  p    p−1 ¯                        0<ς k <ς
                                                                             ∞      p  X
                     + L ˜p E∥x ς 1  , x ς 2  , . . . x ς n ∥ + 2  M g
                                                                              X
                                 ¯
                                                                                                               p
                             p
                                                                                              2 −β 2 (ς−ς k )
                                            a e
                     × (E∥φ∥ + L ˜p )] + 2 p−1 p  −pβ 2 ς [E∥x 1 ∥ p   ≤ a p     L 2  q      L e              ∥ .
                                             2                             2       k          k          E∥x ς k
                                          p
                            p
                                 ¯ p
                     + E∥η∥ + M (1 + M ) sup E∥x ϑ ∥     p                    k=1      0<ς k <ς
                                  g       σ 1                                 n
                                             ϑ∈[0,ς 1 ]              p     p−1   p−1  p  −pβ 1 ς   p
                                                              E∥x(ς)∥ ≤ 8       3    a e     [E∥φ∥
                                                                                      1
                         p  1−p   p       p
                     + [a β     [L (1 + M )]
                         2  2     f       σ 2                               ¯                  ∥ p
                                                                         + L ˜p E∥x ς 1  , x ς 2  , . . . , x ς n
                         p  ˜  1−  p 2 ¯
                     + a C p β 2  L G ]ϑ                                 + 2 p−1 ¯      p   ¯
                                                                               M g (E∥φ∥ + L ˜p )]
                         2
                           ς
                                                                         + 2   a e      [E∥x 1 ∥ + E∥η∥ ]
                          Z                                                 p−1 p  −pβ 2 ς     p       p
                                                                                 2
                                                 p
                        ×   e −β 2 (ς−ϑ)  sup E∥x ϑ ∥ dϑ
                                     ϑ∈[0,ς 1 ]                    ¯ p       p              p
                          0                                     + M (1 + M ) sup E∥x ϑ ∥
                                                                     g
                                                                             σ 1
                         p  −p     pH−1 ˆ                                       ϑ∈[0,ς 1 ]
                     + a β  2  CHς     L}.             (10)                                          p
                         2
                                                                                            p
                                                                             p
                                                                    p
                                                                                     p
                                                                                              ˜
                                                                + [a β 1−p  [L (1 + M )] + a C p β 1− 2 ¯
                                                                                                      L G ]
                                                                    2  2     f       σ 2    2     2
            Then, the integral term in the above inequality         ς
                                                                   Z
            (10) will be reduced to                                   −β 2 (ς−ϑ)          p
                                                                ×    e         sup E∥x ϑ ∥ dϑ
                                                                              ϑ∈[0,ς 1 ]
                                                                   0
                              h      p
                     p
              E∥x(ς)∥ ≤ 6  p−1  3 p−1  a e −pβ 1 ς [E∥φ∥ p                                ∞     p
                                                                                          X
                                     1                              p  −p     pH−1 ˆ    p      1  q
                                                                + a β  2  CHς     L + a 1     L k
                                                                    2
                         ¯                  ∥ p
                       + L ˜p E∥x ς 1  , x ς 2  , . . . , x ς n                           k=1
                                                                          1 −β1(ς−ς k )
                       + 2 p−1 ¯      p   ¯                     ×   X    L e        E∥x ς k ∥ p
                             M g (E∥φ∥ + L ˜p )]
                                                                          k
                          p−1 p  −pβ 2 ς    p        p             0<ς k <ς
                       + 2   a e      [E∥x 1 ∥ + E∥η∥ ]
                              2
                                                                      ∞     p
                                          i                           X          X                       o
                          p  −p     pH−1 ˆ                          p      2  q        2 −β 2 (ς−ς k )  p
                       + a β   CHς       L                      + a 2     L k         L e        E∥x ς k ∥  .
                                                                                       k
                          2  2
                                                                      k=1      0<ς k <ς
                       ≤ M 1 e −pβ 1 ς  + M 2 e −pβ 2 ς , β 1 , β 2 ≥ 0,                                 (11)
            where
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