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+% -*-latex-*- Put EMACS into LaTeX-mode
+% Verbal description for system Poly (Poly_desc.tex)
+% Generated by MTT on Thu Mar 19 13:24:59 GMT 1998.
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+   The acausal bond graph of system \textbf{Poly} is
+   displayed in Figure \Ref{Poly_abg} and its label
+   file is listed in Section \Ref{sec:Poly_lbl}.
+
+This four-port component computes the tempertature following a
+polytropic expansion using:
+\begin{equation}
+  T_2 = T_1 \left ( \frac{P_2}{P_1} \right )^\alpha
+\end{equation}
+where $\alpha = \frac{n-1}{n}$ and $n$ is the coefficient of
+polytropic expansion.