Abstract The authors consider the nonlinear systems [AKx·D6]=h(y)-F(x),=-g(x) in which g(x) may be not differentiable and the system can be nonsymmetric. Some conditions which ensure that there exists an...Abstract The authors consider the nonlinear systems [AKx·D6]=h(y)-F(x),=-g(x) in which g(x) may be not differentiable and the system can be nonsymmetric. Some conditions which ensure that there exists an infinite number of limit cycles are obtained. A problem about center focus put forward by R. Conti has been answered.展开更多
文摘Abstract The authors consider the nonlinear systems [AKx·D6]=h(y)-F(x),=-g(x) in which g(x) may be not differentiable and the system can be nonsymmetric. Some conditions which ensure that there exists an infinite number of limit cycles are obtained. A problem about center focus put forward by R. Conti has been answered.
