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Nodal dynamics, not degree distributions, determine the structural controllability of complex networks
Noah J Cowan1, Erick J Chastain, Daril A Vilhena
1Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America. ncowan@jhu.edu
Plos One
|July 5, 2012
Summary
Structural controllability analysis of complex networks suggests a single input is sufficient for control. However, the study emphasizes the importance of assessing near-uncontrollability and unobservability in real-world systems.
Area of Science:
- Network Science
- Control Theory
- Systems Biology
Background:
- Structural controllability is a framework for analyzing complex network control.
- Its application to real-world networks often suggests minimal control inputs are needed.
Purpose of the Study:
- To critically evaluate the practical implications of structural controllability in complex systems.
- To highlight limitations of the framework and propose alternative analytical focuses.
Main Methods:
- Analysis of structural controllability in diverse complex networks.
- Theoretical examination of control input requirements.
- Discussion of system properties beyond generic controllability.
Main Results:
- The structural controllability framework often concludes a single input is sufficient for control.
- This finding aligns with controllability being a generic system property.
- The study identifies limitations in applying this to real-world scenarios.
Conclusions:
- While structurally controllable, real-world systems may be almost uncontrollable or unobservable.
- Focus should shift to assessing near-uncontrollability and near-unobservability.
- Investigating almost pole-zero cancellations is crucial for practical control analysis.
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