Fig. 2From: A loop enhancement strategy for network robustnessIllustration of our proposed methods. a BP Non-preserving, b BP Preserving. The nodes with larger \(q^0_i\) and \(q^0_j\) and the edges between them are filled with red, while the nodes with smaller \(q^0_k\) and \(q^0_l\) and the edges between them are filled with blueBack to article page