Active Sliding Mode for Synchronization of a Wide Class of Four-Dimensional Fractional-Order Chaotic Systems

Figure 7

Phase portraits of the integer-order Lorenz system.

(a) 𝑥_𝑠-𝑦_𝑠-𝑧_𝑠

(b) 𝑦_𝑠-𝑧_𝑠-𝑤_𝑠