Annals of Biomedical Engineering

, Volume 5, Issue 2, pp 130–143 | Cite as

On the interpretation of kernels

I. Computer simulation of responses to impulse pairs
  • George Hung
  • Lawrence Stark
  • Pieter Eykhoff


A method is presented for the use of a unit impulse response and responses to impulse pairs of variable separation in the calculation of the second-degree kernels of a quadratic system. A quadratic system may be built from simple linear terms of known dynamics and a multiplier. Computer simulation results on quadratic systems with building elements of various time constants indicate reasonably that the larger time constant term before multiplication dominates in the envelope of the off-diagonal kernel curves as these move perpendicular to and away from the main diagonal. The smaller time constant term before multiplication combines with the effect of the time constant after multiplication to dominate in the kernel curves in the direction of the second-degree impulse response, i.e., parallel to the main diagonal. Such types of insight may be helpful in recognizing essential aspects of (second-degree) kernels; they may be used in simplifying the model structure and, perhaps, add to the physical/physiological understanding of the underlying processes.


Computer Simulation Time Constant Impulse Response Large Time Constant Term 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Academic Press, Inc. 1977

Authors and Affiliations

  • George Hung
    • 1
  • Lawrence Stark
    • 1
  • Pieter Eykhoff
    • 1
  1. 1.Departments of Physiological Optics and Engineering ScienceUniversity of CaliforniaBerkeley

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