 problem $$\label{Equ00} \partial _t { f ^\varepsilon}+ { \mathrm{div}_x}\{{ f ^\varepsilon}v\} + { \mathrm{div}_v}\{ { f ^\varepsilon}a\} + \frac{0}{{ \varepsilon}} { \mathrm{div}_v}\{ { f ^\varepsilon}{ (\alpha - \beta |v|^0) v}\} = 0,\;\;(t,x,v) \in {{{\bf}R}}_+ \times {{{\bf}R}}^d \times {{{\bf}R}}^d$$ $$\label{Equ00} { 