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arXiv · 1909.03565

Computation of the Distance-based Bound on Strong Structural Controllability in Networks

Abstract

In this paper, we study the problem of computing a tight lower bound on the dimension of the strong structurally controllable subspace (SSCS) in networks with Laplacian dynamics. The bound is based on a sequence of vectors containing the distances between leaders (nodes with external inputs) and followers (remaining nodes) in the underlying network graph. Such vectors are referred to as the distance-to-leaders vectors. {We give exact and approximate algorithms to compute the longest sequences of distance-to-leaders vectors, which directly provide distance-based bounds on the dimension of SSCS. The distance-based bound is known to outperform the other known bounds (for instance, based on zero-forcing sets), especially when the network is partially strong structurally controllable. Using these results, we discuss an application of the distance-based bound in solving the leader selection problem for strong structural controllability. Further, we characterize strong structural controllability in path and cycle graphs with a given set of leader nodes using sequences of distance-to-leaders vectors. Finally, we numerically evaluate our results on various graphs.

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BibTeXRIS

Mudassir Shabbir, Waseem Abbas, A. Yasin Yazicioglu, Xenofon Koutsoukos. 2019-09-08. Computation of the Distance-based Bound on Strong Structural Controllability in Networks. https://arxiv.org/abs/1909.03565

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