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\sigma_{dc}(E) = \sigma_a + \sigma_b\space exp\left(-\frac{E_0}{E}\right)  \end{equation}  The CDW transport (depinning) problem with the presence of applied voltage is modeled by a classical single particle sliding down the periodic lattice potential with displacement $x$ \cite{Rice_1975}. $x$.  \begin{equation}  m \frac{d^2 x}{d^2 t} + \Gamma \frac{dx}{dt} + \omega_p^2 x = e^* \left(\frac{V_{applied}}{l}\right)  \end{equation}