, with the parameters ![ $$\\lambda \\in \\mathbb{R}^{+}$$ ](A000000_0_En_0_Chapter_IEq00.gif) and ![ $$\\mu \\in \\mathbb{R}^{+}$$ ](A000000_0_En_0_Chapter_IEq00.gif) being associated with the shape and the shift of the exponential function, respectively. 