Page 365 - Mathematical Techniques of Fractional Order Systems
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356  Mathematical Techniques of Fractional Order Systems


                                               25
                                               20
                10                             15
                 0                             10
                –10                            5
              y 23 (t)  –20                  y 22 (t)  0
                                               –5
                –30
                                              –10
                –40
                 40                           –15
                   20                       40
                                              –20
                       0               20
                        –20       0
                   y (t)                      –25
                    22     –40  –20  (t)        –20  –10  0    10   20   30
                                   y 21
                                                            y (t)
                                                            21
                          (A)                               (B)
                 5                              5
                 0                              0
                –5                             –5
                –10                            –10
               y 23 (t)  –15                 y 23 (t)  –15
                –20                            –20
                –25                            –25
                –30                            –30
                –35                            –35
                 –20  –10   0   10   20   30    –30  –20  –10  0  10  20  30
                               (t)                          y (t)
                             y 21                            22
                            (C)                             (D)
            FIGURE 12.4 Phase portraits of Volta’s system at α 5 0:99: (A) in y 21 2 y 22 2 y 23 space, (B)
            in y 21 2 y 22 plane, (C) in y 21 2 y 23 plane, (D) in y 22 2 y 23 plane.
               The fractional order Lu hyperchaotic system (Pan et al., 2011) and the
            fractional order 4D Integral order hyperchaotic system (Deng et al., 2009)
            are taken as the corresponding two response systems as
                               α
                              d x 31
                               dt α  5 a 31 ðx 32 2 x 31 Þ 1 x 34 1 u 11
                               α
                              d x 32
                               dt α  52 x 31 x 33 1 a 33 x 32 1 u 12
                               α                                     ð12:14Þ
                              d x 33
                               dt α  5 x 31 x 32 2 a 32 x 33 1 u 13
                               α
                              d x 34
                                   5 x 31 x 33 1 a 34 x 34 1 u 14 ;
                               dt α
            where u 11 ; u 12 ; u 13 ; u 14 are control functions, x 31 ; x 32 ; x 33 , and x 34 are
            states variables and a 31 ; a 32 ; a 33 , and a 34 are constant parameters. The
            phase portraits of (12.14) in x 31 2 x 32 2 x 33 , x 31 2 x 32 2 x 34 , x 31 2 x 33 2 x 34 ,
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