Hi there;

I wonder if anyone can help me find out how I can apply several derivatives in a boundary; in a 1D problem

\frac{\partial \phi}{\partial x}=\alpha

\frac{\partial^2 \phi}{\partial x^2}=\beta

\frac{\partial^3 \phi}{\partial x^3}=\gamma

How can I impose them to a single boundary?

And does it make sense? If so, is there any consideration on the element type that should be used?