| Contents |
| Self similar fractals are often used in modeling porous materials. However, the assumption of strict self similarity could be too restricting. So, we present several models of random fractals which could be used instead. After recalling the classical approaches of random homogenous and recursive random fractals, we show how to interpolate between these two models with the help of so called V-variable fractals. This concept (developed by Barnsley, Hutchinson & Stenflo) allows the definition of new families of random fractals, hereby the parameter V describes the degree of "variability" of the realizations. We discuss how the degree of variability influences the spectral asymptotics of corresponding Dirichlet forms. Moreover, on--diagonal heat kernel estimates are presented. |
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