Page 539 - Mathematical Techniques of Fractional Order Systems
P. 539

Chaotic Properties of Various Types of Hidden Attractors Chapter | 17  519

































             FIGURE 17.3 (A) MLE versus the parameter a for system (2). (B) Time evolution of Lyapunov
             exponents at a 5 0.35. (C) Phase portrait at a 5 0.05. (D) the corresponding time evolution of LEs.

              (A)                  (B)                  (C)
                0.14                  0.1                 30
                0.12
                                      0.08                20
                 0.1
                0.08                  0.06                10
             MLE  0.06             MLE  0.04            y  0
                0.04
                                      0.02               –10
                0.02
                 0                     0                 –20
                  0.9  0.95  1  1.05  1.1  2  2.02 2.04 2.06 2.08  2.1  –20 –10  0  10  20  30
                          a                    a                   x
             FIGURE 17.4 MLE versus a in different ranges for system (16). (A) 0.9 , a , 1.1; (B)
             2 , a , 2.1; and (C) Phase portrait at a 5 5.
             17.4.4 A Dissipative Hidden Attractor With Single
             Stable Equilibrium Point: System (19)
             The equations of the system was given in Jafari et al. (2015) with constant
             coefficients instead of parameters. The coefficients 0.4 and 0.6 that appear in
             the system’s equations in Table 17.2 are replaced by parameters a and b,
             respectively. Fig. 17.5 shows that the ranges of both coefficients that corre-
             spond to positive MLE values are limited.


             17.5 SENSITIVITY TO FRACTIONAL ORDERS
             In this section, we discuss the sensitivity of the selected systems to fractional
             orders. Numerical simulations are used to identify when they generate
   534   535   536   537   538   539   540   541   542   543   544