ADDED   mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_desc.tex
Index: mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_desc.tex
==================================================================
--- /dev/null
+++ mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_desc.tex
@@ -0,0 +1,21 @@
+% Verbal description for system Weir (Weir_desc.tex)
+% Generated by MTT on Thu Jul 3 10:27:26 BST 1997.
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+   The acausal bond graph of system \textbf{Weir} is
+   displayed in Figure \Ref{Weir_abg} and its label
+   file is listed in Section \Ref{sec:Weir_lbl}.
+   The subsystems are listed in Section \Ref{sec:Weir_sub}.
+
+Each weir is modeled by two {\bf ISW} components: one for flow
+left-right and one for flow right-left. The switching is such that
+they become non-return valves when the left hand (respectively
+right-hand) level reaches an appropriate value. The parameters appear
+in Section \Ref{sec:Weir_numpar.txt} and the switching conditions in
+Section \Ref{sec:Weir_input.txt}.

ADDED   mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_lbl.txt
Index: mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_lbl.txt
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+++ mttroot/mtt/lib/examples/Hybrid/Weirs/Weir_lbl.txt
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+%SUMMARY Weir: Tank with weirs (hybrid)
+%DESCRIPTION Each weir is modeled by two {\bf ISW} components: 
+%DESCRIPTION one for flow left-right 
+%DESCRIPTION one for flow right-left. 
+%DESCRIPTION The switching is such that they become non-return valves 
+%DESCRIPTION when the left hand (respectively right-hand) level reaches 
+%DESCRIPTION an appropriate value
+%% Label file for system Weir (Weir_lbl.txt)
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Each line should be of one of the following forms:
+%	a comment (ie starting with %)
+%	Component-name	CR_name	arg1,arg2,..argn
+%	blank
+
+
+
+% Component type C
+	tank1		lin	effort,c_1
+	tank2		lin	effort,c_2
+	tank3		lin	effort,c_3
+
+% Component type ISW
+	weir1L		lin	flow,epsilon
+	weir1R		lin	flow,epsilon
+	weir2L		lin	flow,epsilon
+	weir2R		lin	flow,epsilon
+
+% Component type R
+	leak		lin	flow,r_l
+
+% Component type SS
+	f		internal	external
+
+	p1		external	0
+	p2		external	0
+	p3		external	0
+