  We investigate the response behavior of an Ising system, driven by an
oscillating field, on a small-world network, with particular attention to the
effects of the system size. The responses of the magnetization to the driving
field are probed by means of Monte Carlo dynamic simulations with the rewiring
probability varied. It is found that at low and high temperatures the occupancy
ratio, measuring how many spins follow the driving field, behaves monotonically
with the system size. At intermediate temperatures, on the other hand, the
occupancy ratio first grows and then reduces as the size is increased,
displaying a resonance-like peak at a finite value of the system size. In all
cases, further increase of the size eventually leads to saturation to finite
values; the size at which saturation emerges is observed to depend on the
temperature, similarly to the correlation length of the system.
