In  this  paper a  non-linear  model  with  fractional  order  is  presented  for  analyzing  and  controlling the  spread  of  HIV virus.  Both  the  disease-free  equilibrium and the endemic equilibrium are  found  and  their  stability is  discussed. The basic reproduction number , which is a function of the constant parameters in the model, plays an essential  role in the stability of  the ...

In this paper, an SIR epidemic model with an infectious period and a non-linear Beddington-DeAngelis type incidence rate function is considered. The dynamics of this model depend on the reproduction number R0. Accurately, if R0 < 1, we show the global asymptotic stability of the disease-free equilibrium by analyzing the corresponding characteristic equation and using compa...

We use `p estimates together with Brascamp-Lieb inequalities to obtain bounds on the variance of the solution u" to the elliptic equation r" a(x="; ')r"u" = r" f . The variance is shown to be O("r) where the exponent r depends on the contrast of a(x; '). In two dimensions, we show that variance of the Greens function of the above elliptic operator is bounded. We also obtain decay rates for the ...

in this study a simple and general chemical association theory is introduced. the concept of infinite equilibrium model is re-examined and true mole fractions of associated species are calculated. the theory is applied to derive the distribution function of associated species. as a severe test the application of presented theory to the van der waals mixture model is introduced in order to perfo...

We propose a coupling scheme, where the advantages of the coherent Green’s function formalism are combined with the ability of the Wigner formalism to account for phasebreaking processes of interaction with phonons and other lattice imperfections. The Green’s function formalism is used to calculate the coherent Wigner function which provides the initial condition in an equation, from which corr...