Bifurcation Analysis of a Van der Pol-Duffing Circuit with Parallel Resistor

Figure 6

(a) Hopf surface 𝛽=𝛽_𝑐 and curves {𝑙₁=0} (solid) and {𝑙₂=0} (dashed) for 𝛼=2. (b) Hopf surface 𝛽=𝛽_𝑐 and curves {𝑙₁=0} (solid) and {𝑙₂=0} (dashed) for 𝛼=3.

(a)

(b)