Fig. 8
From: Transforming the canonical piecewise-linear model into a smooth-piecewise representation

First derivatives: \(lne^{\prime}\) of \(lne\) for \(k_{1} = 1\), \(lch^{\prime}\) of \(lch\) for \(k_{2} = 1\), and \(th^{\prime}\) of \(th\) for \(k_{3} = 0.4\)