In this paper, we consider a stochastic SIS epidemic model with vaccination. We prove that the densities of the distributions of the solution can converge in L1 to an invariant density under appropriate conditions. Also we find the support of the invariant density.

Magnetic properties of a biaxial spin-1 system in an applied transverse field are investigated by using the effective-field theory with correlations on the basis of the differential technique. We have studied the effects of the transverse field on the phase diagrams, internal energy, and...