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+% Verbal description for system Cycle (Cycle_desc.tex)
+% Generated by MTT on Thu Dec 4 15:59:55 GMT 1997.
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% Revision 1.1  1997/12/08  09:37:04  peterg
+% Initial revision
+%
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+   The acausal bond graph of system \textbf{Cycle} is
+   displayed in Figure \Ref{Cycle_abg} and its label
+   file is listed in Section \Ref{sec:Cycle_lbl}.
+   The subsystems are listed in Section \Ref{sec:Cycle_sub}.
+The system has two heat engine ports: 
+\begin{enumerate}
+\item \textbf{[Heat]} and
+\item \textbf{[Work]}
+\end{enumerate}
+By convention, energy flows in to the \textbf{[Heat]} port and out of
+the \textbf{[Work]} port. Both ports are true energy ports.
+
+
+The subsystem \textbf{CU} (Section \Ref{sec:CU}) is a two-port
+component describing an ideal gas. It has two energy ports which, with
+integral causality correspond to
+\begin{enumerate}
+\item Entropy flow in; temperature out
+\item Volume rate of change in; pressure out
+\end{enumerate}
+
+Four \textbf{SS} components are set up as sensors to measure the
+important quantities pertaining to the cycle:
+\begin{enumerate}
+\item \textbf{S} to measure the integrated entropy flow
+\item \textbf{T} to measure the (absolute) temperature
+\item \textbf{V} to measure the integrated volume change
+\item \textbf{P} to measure the pressure
+\end{enumerate}
+
+   \begin{table}[htbp]
+     \begin{center}
+       \leavevmode
+       \begin{tabular}{|l|l|l|l|l|}
+         \hline
+         Cycle & Compression & Heating & Expansion & Cooling \\
+         \hline
+         Otto & II & II & II & II \\
+         Carnot & II & DI & II & DI \\
+         Diesel & II & ID & II & II \\
+         Joule & II & ID & II & ID \\
+         \hline
+       \end{tabular}
+       \caption{Cycles and their causality}
+       \label{tab:cycles}
+     \end{center}
+   \end{table}
+   
+   A number of cycles can be built depending on the causality of the
+   two ports \textbf{[Heat]} and \textbf{[Work]} of \textbf{Cycle}
+   Some possible cycles listed in Tables \Ref{tab:cycles} where each
+   table entry gives the causality on the heat and work ports
+   respectively.
+