When the memory set is a fractal, whether the generating mappings of the me
mory set are linear or non-linear, a fractional integral approximation of f
lux related on the fractal memory set is obtained. The fractional exponent
nu is dependent only on the first generating mapping and the first weight o
f the self-similar measure. Moreover, a fine approximation of flux in terms
of fractional integrals is also obtained. This approximation is dependent
on all generating mappings and all weights of self-similar measure. This es
tablishes the relationship between the fractional integral and the fractal
structure of the memory set. (C) 2000 Elsevier Science B.V. All rights rese
rved.