Page 227 - Mathematical Techniques of Fractional Order Systems
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216  Mathematical Techniques of Fractional Order Systems


               Step 1: Π 1 is completely continuous. First, to prove that Π 1 is continu-
                                                    0
            ous. Let fz n g be a xsequence such that z n -z in C as n-N. Then for tAJ,
                                                    b
             EjðΠ 1 z n ÞðtÞ 2 ðΠ 1 zÞðtÞj # 2E   Ð    0 t  ½fðs; z n s 1y s Þ2fðs; z s 1y s ފds   2
                           2

                                                                 2

                                      1  Ð  t  α21  Ð    s
                               1 2E  ΓðαÞ 0  ðt2sÞ  2N  σðτ; z τ 1y τ ÞdWðτÞ ds

                                Ð  t                2
                            # 2b  E fðs; z n s 1y s Þ2fðs; z s 1y s Þ ds


                                0
                                  2b α  ð t      ð    s                     2
                                              E
                               1        ðt2sÞ  α21    ½σðτ; z n τ  1y τ Þ2σðτ; z τ 1y τ ފdWðτÞ ds

                                   2
                                 αΓ ðαÞ 0         2N
                                                              2
            since f and σ are continuous, one has OðΠ 1 z n ÞðtÞ 2 ðΠ 1 zÞðtÞO -0 as n-N:
                                                              b
                                                               0
            Now, to prove Π 1 maps bounded sets into bounded sets in C . Indeed, it is
                                                               b
            enough to prove that for any q . 0, there exists a positive constant δ such
            that for each zAB q , one has ðΠ 1 zÞAB δ . Let zAB q , since f and σ are continu-
            ous, for each tAJ
                                                        2
                                                                       2
                        2        2      1  Ð  t  α21 BðsÞuðsÞds  1 4E   Ð    t  fðs; z s 1y s Þds

                                     ΓðαÞ 0  ðt2sÞ          0
                 EjðΠ 1 zÞðtÞj # 4Ejφð0Þj 1 4E

                               4b α  ð t      ð    s           2
                                           E
                            1        ðt2sÞ  α21    σðτ; z τ 1y τ ÞdWðτÞ ds

                                2
                              αΓ ðαÞ 0         2N
                                        2           1 12  1        3 2
                                         0
                                               ðα21Þp  p          1
                                       2  ð t   p21       ð t
                                 2
                                                               p
                          # 4Ejφð0Þj 1  4OBO 6 B  ðt2sÞ  dsA  EjuðsÞj ds  p 7
                                                    C
                                        6
                                                                   7
                                     2
                                         @
                                    Γ ðαÞ  4  0           0        5
                                Ð  t        2
                            1 4b  E fðs; z s 1y s Þ ds


                                0
                                 α  ð t    "       ð    s         2 #
                               4b
                            1   2    ðt2sÞ α21  2M R 1 2E    σðτ; z τ 1y τ ÞdWðτÞ    ds
                              αΓ ðαÞ 0               0
                                         2αp22  ! 2p22
                                    OBO 2  p      p
                                 2
                          # 4Ejφð0Þj 1 4  b   p21   OuO 2
                                     2
                                    Γ ðαÞ     αp21    L p ðJ;UÞ
                                            2
                                Ð  t
                            1 4b  nðsÞΛ f ðOz s 1 y s O Þds
                                0           C h
                               8b α  ð t   h                    i
                                                              2
                            1        ðt2sÞ α21  M R 1 TrðQÞmðsÞΛ σ ðOz s 1 y s O Þ ds
                                2                             C h
                              αΓ ðαÞ 0
                                         2αp22  ! 2p22
                                    OBO 2  p      p
                                              p21
                                                              2
                                 2

                          # 4Ejφð0Þj 1 4  2  b  αp21  OuO 2 L p ðJ;UÞ  1 4b OnO N Λ f ðq Þ
                                    Γ ðαÞ
                                8b 2α

                            1  2     ½ M R 1 TrðQÞOmO N Λ σ ðq ފ 5 δ , N
                              Γ ðα 1 1Þ
                          2
            thus EjðΠ 1 zÞðtÞj # δ and hence Π 1 zAB δ . Now, to prove that Π 1 maps
                                                0
            bounded sets into equicontinuous sets of C . Let t 1 ; t 2 AJ; t 2 . t 1 and let B q
                                                b
            be a bounded set. Let zAB q , then if E . 0 and E # t 1 # t 2 , one has
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