Invariance Properties of Practical Test-Functions Used for Generating Asymmetrical Pulses

  • Stefan Pusca
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3980)


This paper presents a heuristic algorithm for generating asymmetrical practical test functions using MATLAB procedures. Based on the fact that differential equations can generate only functions similar to test functions (defined as practical test functions), the invariance general properties suitable for generating symmetrical pulses as related to the middle of the working interval are presented. Then some possibilities for obtaining asymmetrical pulses as related to this middle of the working interval using the derivative of such symmetrical pulse are studied, for certain differential equations corresponding to second order systems (with unity-step input and for an input represented by a gaussian pulse). Finally it is shown that we can obtain an oscillating system by joining such working intervals and restoring the initial null conditions for a second order system, in an adequate manner.


Solitary Wave Order System Invariance Property Null Condition Limited Time Interval 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Stefan Pusca
    • 1
  1. 1.Department of PhysicsPolitehnica UniversityBucharestRomania

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