The modelling and analysis of fractional-order control systems in   frequency domain
  This paper deals with fractional-order controlled systems and fractional-order controllers in the frequency domain. The mathematical description by fractional transfer functions and properties of these systems are presented. The new ways for modelling of fractional-order systems are illustrated with a numerical example and obtained results are discussed in conclusion. 
I. Petras, L. Dorcak (Technical University of Kosice), P. O'Leary   (University of Leoben), B.M. Vinagre (University of Extr...