this study was designed and conducted to find out if there is any significant relationship between iranian efl learners preferance for one of the three degrees of obtrusiveness in foreign language instruction (focus on form, forms and meaning) and their preferred experiential learing style. to collect the data two questionnaires were used. the first one on the degree of obtrusiveness and the se...

In this paper we investigate a kind of boundary value problem involving a fractional differential equation.  We study the existence of positive solutions of the problem that fractional derivative is the Reimann-Liouville fractional derivative. At first the green function is computed then it is proved that the green function is positive. We present necessary and sufficient conditions for existen...