Enhancing speed of pinning synchronizability: low-degree nodes with high feedback gains

TL;DR

This paper introduces a method to enhance the speed of pinning controllability in complex networks by optimizing feedback gains, revealing that low-degree nodes can be highly influential and improve control efficiency.

Contribution

It proposes a linear matrix inequality approach to optimize feedback gains for all nodes, improving pinning controllability speed and challenging traditional node selection strategies.

Findings

Low-degree nodes can achieve high feedback gains.

Selecting nodes with high feedback gains accelerates control.

The method outperforms traditional large-degree and betweenness-based selections.

Abstract

Controlling complex networks is of paramount importance in science and engineering. Despite recent efforts to improve controllability and synchronous strength, little attention has been paid to the speed of pinning synchronizability (rate of convergence in pinning control) and the corresponding pinning node selection. To address this issue, we propose a hypothesis to restrict the control cost, then build a linear matrix inequality related to the speed of pinning controllability. By solving the inequality, we obtain both the speed of pinning controllability and optimal control strength (feedback gains in pinning control) for all nodes. Interestingly, some low-degree nodes are able to achieve large feedback gains, which suggests that they have high influence on controlling system. In addition, when choosing nodes with high feedback gains as pinning nodes, the controlling speed of real systems is remarkably enhanced compared to that of traditional large-degree and large-betweenness selections. Thus, the proposed approach provides a novel way to investigate the speed of pinning controllability and can evoke other effective heuristic pinning node selections for large-scale systems.