Figure 4

Chaotic attractors of system ( 3 ) in 3D spaces with \(\pmb{u_{1} = 0.2}\) , \(\pmb{u_{2} = 0.5}\) , \(\pmb{q_{1} = 5.9}\) , \(\pmb{q_{2} = 9.15}\) , \(\pmb{\varepsilon_{1} = 0.5}\) , \(\pmb{\varepsilon_{2} = 0.1}\) and the initial state \(\pmb{( x_{1} ( 0 ),x_{2} ( 0 ),w_{1} ( 0 ),w_{2} ( 0 ) ) = ( 2.2,2.0,10.5,20 )}\) .