Introduction
  
    - Hybrid systems containing state events:
      
	- modelling still nontrivial in many simulation
	  programs
 
	- structural changes especially difficult
 
	- adressed by Argesim C21 benchmark
 
	- example models
	  
	    - bouncing ball
 
	    - RLC circuit with diode
 
	    - rotating pendulum with free flight phase