V. Sapozhnikov et E. Foufoulageorgiou, STUDY OF SELF-SIMILAR AND SELF-AFFINE OBJECTS USING LOGARITHMIC CORRELATION INTEGRAL, Journal of physics. A, mathematical and general, 28(3), 1995, pp. 559-571
We suggest a logarithmic correlation integral z(x, y) as a good tool f
or investigating self-affine and self-similar objects. First, it enabl
es us to extract fractal exponents v(x) and v(y) from one pattern of a
n object having any topology. Second, we show that the integral z(x, y
) which completely characterizes a monofractal object provides more in
formation on the density correlation properties of the object than jus
t the exponents v(x) and v(y). We quantify this additional information
by introducing two parameters: delta, characterizing the object's ani
sotropy of a nonscaling nature, and kappa characterizing the curvature
of the logarithmic correlation integral of the object. We demonstrate
that the four parameters: v(x), v(y), delta and kappa provide an effe
ctive parametrization of the logarithmic correlation integral of a sel
f-affine monofractal object. We give some examples of self-affine obje
cts, having the same fractal exponents v(x) and v(y) but different par
ameters delta and kappa indicating the differences in the correlation
properties of the objects. We demonstrate that even a self-similar obj
ect showing isotropic scaling (v(x) = v(y)) may have the non-scaling a
nisotropy parameter delta different from zero, which indicates that th
e object has an asymmetric integral z(x, y) and, therefore, different
correlation properties in different directions. It is shown that the e
quality kappa = 0 outlines a class of objects for which the exponents
v(x) and v(y) are not defined uniquely. For instance, such objects can
be treated as both self-similar and self-affine. If kappa is close to
zero, estimation of the exponents v(x) and v(y) may become problemati
c. Relationships connecting the exponents v(x), v(y) and fractal dimen
sions of the projection and cross section of an object are established
.