ABSTRACT
To minimize the effects of non-stationary and obtain meaningful statistical analyses, the time series data have been logarithmically transformed and seconddifferenced. After the logarithmical transformation and the second-differenced of the data series, it is possible to evaluate the CCF functions (ρi,j(h)) for different combinations of the restoration curves. Four equations for the evaluation of the interdependency index Si,j among different infrastructures are proposed and compared with the one which has been proposed by Dueñas-Osorio & Kwasinski (2012) Eq. (1).
