ADDED   mttroot/mtt/lib/examples/Control/PPP/Nonlinear/rcPPP/rcPPP_desc.tex
Index: mttroot/mtt/lib/examples/Control/PPP/Nonlinear/rcPPP/rcPPP_desc.tex
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+% Verbal description for system rcPPP (rcPPP_desc.tex)
+% Generated by MTT on Sun Aug 24 11:03:55 BST 1997.
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% %% Revision 1.1  1997/08/24 10:27:18  peterg
+% %% Initial revision
+% %%
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+The acausal bond graph of system \textbf{rcPPP} is
+displayed in Figure \Ref{rcPPP_abg} and its label
+file is listed in Section \Ref{sec:rcPPP_lbl}.
+The subsystems are listed in Section \Ref{sec:rcPPP_sub}.
+The system \textbf{rcPPP} is based on the simple electrical rc circuit shown in
+Figure \Ref{rcPPP_abg}. 
+
+It can be regarded as a single-input
+single-output system with input $e_1$ and output $e_2$.
+The bond graph in Figure \Ref{rcPPP_abg} is augmented with the {\em
+open-loop\/} controller comprising
+\begin{itemize}
+\item two effort source \textbf{Se} components ``u1'' and ``u2''
+\item two effort amplifier \textbf{AE} components ``ppp\_1'' and `ppp\_2''
+\end{itemize}
+
+This is a \emph{linear} system; but it is used to illustate
+\emph{nonlinear} PPP control. Not surprisingly, the \emph{nonlinear}
+PPP control gives nearly the same result (Section \Ref{sec:rcPPP_nppp.ps})
+as linear open and closed-loop control.
+
+
+
+
+