1. INTRODUCTION
Driven by a considerable number of data and powerful computing resources, deep learning has made a breakthrough in many application fields with its powerful representation ability [1]. With the increasing application of non-Euclidean data, most deep learning models have limited performance in processing graph data [2]. As a representative method of combining deep learning with graph data, the emergence of GCN promotes neural network technology in graph data learning tasks. Recent years have seen increasing attention to graph convolutional networks, such as social networks [3], protein molecules [4], and transportation networks [5].