Component \textbf{FMRT} is a two port thermal resistor with true power
bonds. Internally, it has a pseudo Bond Graph representation, and the
corresponding thermal resistance just acts as an ordinary one-port
\textbf{R} component.

The resistance $r$ is modulated by a flow variable $f$ on the [mod] port
so that the {\em conductance\/} $\sigma$ is:
\begin{equation}
  \sigma = \frac{f}{r} 
\end{equation}

