Global dynamic behavior particularly the bifurcation of periodic orbits of a parallel blower system is studied using a piecewise linear model and the one-dimensional map defined by the Poincare map. First several analytical tools are presented to numerically study the bifurcation process particularly the bifurcation point of the fixed point of the Poincare map. Using two bifurcation diagrams and a bifurcation set, it is shown how periodic orbits bifurcate and leads to chaotic state. It is also shown that the homoclinic bifurcations occur in some parameter regions and that the Li & Yorke conditions of the chaotic state hold in the parameter region which is included in the one where the homoclinic bifurcation occurs. Together with the above, the stable and unstable manifolds of a saddle closed orbit is illustrated and the existence of the homoclinic points is shown.

Bifurcations of the periodic solutions of the space-clamped Hodgkin-Huxley equations for the muscle membrane are studied regarding the chloride conductance as a parameter. A limit cycle appears at a Hopf bifurcation and disappears at a homoclinic orbit. With high sodium permeability, a subcritical period doubling bifurcation occurs before it disappears.