A characterization of structural nikol'skiî- besov spaces using fractional derivatives

The Nikol'skiî-Besov spaces Bapq(Rn), 1 0, are defined in terms of modulus of continuity and they are characterized using the partial derivatives of the Poisson integrals. In this work we show a characterizationof the functions of Bapq(Rn) using the Caputo noninteger orderderivative of the Pois...