Page 158 - Mathematical Techniques of Fractional Order Systems
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146  Mathematical Techniques of Fractional Order Systems



                             T  T   T       T
                      5 τ m x ðtÞA 1 x ðt 2 τðtÞÞA τ  Z A 0 xðtÞ 1 A τ xðt 2 τðtÞÞ
                                0
                            t                                          ð5:56Þ
                            ð
                          2     _ xðsÞZ _ xðsÞds
                            t2τ m
               On the other hand, by adding the left sides of (5.10) and (5.11) to the
            time derivative of the Lyapunov functional candidates VðtÞ, where
            VðtÞ 5 V 1 ðtÞ 1 V 2 ðtÞ 1 V 3 ðtÞ, yields
                           ð N
                dVðtÞ             T                T
                      #2 2   ωμðωÞz ðω; tÞPzðω; tÞdω 1 2x ðtÞPðA 0 xðtÞ 1 A τ xðt 2 τðtÞÞÞ
                 dt         0
                          T                T
                        1 x ðtÞQxðtÞ 2 ð1 2 @τ m Þx ðt 2 τðtÞÞQxðt 2 τðtÞÞ
                              T  T   T       T
                        1 τ m x ðtÞA 1 x ðt 2 τðtÞÞA τ  ZðA 0 xðtÞ 1 A τ xðt 2 τðtÞÞÞ
                                 0
                         ð  t                    ð t
                                                      T
                                         T
                        2    _ xðsÞZ _ xðsÞ 1 τ m η ðtÞΓηðtÞ 2  η ðtÞΓηðtÞdsds
                          t2τ m                   t2τðtÞ
                                                             ð  t
                            T
                                   T
                        1 2ðx ðtÞY 1 x ðt 2 τðtÞÞT Þ 3  xðtÞ 2 xðt 2 τðtÞ 2  _ xðsÞds
                                                              t2τðtÞ
                                                                      ð5:57aÞ
                                N
                               ð
                                       T
                                                        T
                           #2 2   ωμðωÞz ðω; tÞPzðω; tÞdω 1 ηðtÞ ϒ 1 ηðtÞ
                                0
                              ð t                                     ð5:57bÞ
                                      T
                            2     ηðt; sÞ Wηðt; sÞds
                               t2τðtÞ
            where

                                          Φ 11  Φ 12
                                     ϒ 1 5                            ð5:58aÞ
                                          Φ 21  Φ 22
                                       2            3
                                        Γ 11  Γ 12  2Y
                                  Ω 1 5 Γ T 12  Γ 22  2T  5           ð5:58bÞ
                                       4
                                         0   0   Z
                                                           T
                                      T    T         T
                              ηðt; sÞ 5 x ðtÞ  x ðt2τðtÞÞ  _ x ðtÞ    ð5:58cÞ
            and
                                         T
                           Φ 11 5 2PA 0 1 τ m A ZA 0 1 2Y 1 τ m Γ 11 1 Q
                                         0
                                         T
                           Φ 12 5 2PA τ 1 τ m A ZA τ 2 2Y 1 τ m Γ 12
                                         0
                                   T         T
                           Φ 21 5 τ m A ZA 0 1 τ m Γ 1 2T
                                   τ
                                             12
                                               T
                                               τ
                           Φ 22 52 Λ 1 Q 2 2T 1 τ m A ZA τ 1 τ m Γ 22
               As a result, sufficient conditions are given such that the inequalities
            VðtÞ . 0 and  dVðtÞ  , 0 are fulfilled for any ηðtÞ 6¼ 0 and ηðt; sÞ 6¼ 0. These two
                        dt
            inequalities are equivalent to ϒ 1 , 0 and Ω 1 $ 0.
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