[01] Simon S. Li, School of Information Management, Nanjing University, Nanjing, China; Jiangsu Key Laboratory of Data Engineering and Knowledge Service, Nanjing, China. [02] Xia Lin, College of Computing and Informatics, Drexel University, Philadelphia, USA. [03] Xiaozhong Liu, School of Informatics and Computing, Indiana University, Bloomington, USA. [04] Fred Y. Ye, School of Information Management, Nanjing University, Nanjing, China; Jiangsu Key Laboratory of Data Engineering and Knowledge Service, Nanjing, China.

Extending the network h-core in single layer weighted networks, a method to extract a multilayer weighted network’s core structure, called h-crystal, has been proposed and verified. By applying the algorithms of h-degree and h-strength to each individual layer, a network’s h-core consisting of all the nodes having the h-degree above within edges and an h-subnet consisting of all the edges having the h-strength above with the nodes adjacent to the edges had been obtained, for each layer, at first. H-crystal is then identified by constructing layer-bridges between the layers’ network h-cores and h-subnets. Via two empirical cases of information networks, it is found that the h-crystals of the networks exist, while their features and properties are revealed.

H-degree, H-strength, Network H-core, H-subnet, H-crystal, Multilayer Networks, Weighted Network, Information Network, Heterogeneous Network

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