Page 559 - Mathematical Techniques of Fractional Order Systems
P. 559

Parameters Identification of Fractional Order Chapter | 18  537


                   Chebychev map          Circl map       Gauss/mouse map
                   1                   1                   1
                x i  0.5            x i  0.5            x i  0.5
                   0                   0                   0
                   0            500    0            500    0            500
                          i                   i                   i
                    Iterative map        Logistic map      Piecewise map
                   1                   1                   1
                x i  0.5            x i  0.5            x i  0.5
                   0                   0                   0
                   0            500    0            500    0            500
                          i                   i                   i
                      Sine map           Singer map        Sinusoidal map
                   1                   1                   1
                x i  0.5            x i  0.5            x i  0.5
                   0                   0                   0
                   0            500    0            500    0            500
                          i                   i                   i
                      Tent map
                   1
                x i  0.5
                   0
                   0            500
                          i
             FIGURE 18.2 Distribution values of chaotic maps.

             3. Hunting prey: In this stage, the wolves have a certain knowledge about
                the prey position and all the wolves walk toward it hunting it. This
                behavior can be formulated mathematically as follows in Eqs. (18.12)
                (18.14) (Mirjalili et al., 2014):
                                       ~    ~ ~     ~
                                      D α 5 jC 1 :X α 2 Xj
                                       ~    ~ ~    ~
                                      D β 5 jC 2 :X β 2 Xj            ð18:12Þ
                                       ~    ~ ~    ~
                                      D δ 5 jC 3 :X δ 2 Xj
                                       ~   ~    ~ ~
                                       X 1 5 X α 2 A 1 :D α
                                       ~   ~    ~ ~
                                       X 2 5 X β 2 A 2 :D β           ð18:13Þ
                                       ~   ~    ~ ~
                                       X 3 5 X δ 2 A 3 :D δ
                                             ~
                                                  ~
                                                      ~
                                    -        X 1 1 X 2 1 X 3
                                    Xðt 1 1Þ 5                        ð18:14Þ
                                                  3
             4. Attacking prey (Exploitation phase): For the last stage, the wolves
                attack the prey. This process is done through decreasing parameter a line-
                arly from 2 to 0, consequently the fluctuation range of A is decreased
                (Mirjalili et al., 2014). The flowchart of the GWO technique is in
                Fig. 18.3
   554   555   556   557   558   559   560   561   562   563   564