Correction: Energy-Optimal Electrical-Stimulation Pulses Shaped by the Least-Action Principle

There is an error in Equation 18. Please view the complete, correct equation here:

$$\Theta \left(x\left(T\right)\right)=\frac{K_{penalty}}{2}{(V_{THR}-V\left(T\right))}^2$$

There is an error in Equation 19. Please view the complete, correct equation here:

$$\begin{array}{l}\mathcal{L}=\Theta (x(T))+{\displaystyle {\mathrm{\int }}_{t=0}^T}\left[f_0(X\mathrm{,}u)-\lambda \text{'}(\frac{d}{dt}X-F(X\mathrm{,}u))\right]dt\\ =\Theta (x(T))+{\left[\lambda \text{'}X\right]}_{t=0}^T+{\displaystyle {\mathrm{\int }}_{t=0}^T}\left[H+\frac{d}{dt}\lambda \text{'}X\right]dt\end{array}$$