This paper describes our system for the EvaHan2024 shared task. We design and experiment with two sequence labeling approaches, i.e., one-stage and two-stage approaches. The one-stage approach directly predicts a label for each character, and the label may contain multiple punctuation marks. The two-stage approach divides punctuation marks into two classes, i.e., pause and non-pause, and separately handles them via two sequence labeling processes. The labels contain at most one punctuation marks. We use pre-trained SikuRoBERTa as a key component of the encoder and employ a conditional random field (CRF) layer on the top. According to the evaluation metrics adopted by the organizers, the two-stage approach is superior to the one-stage approach, and our system achieves the second place among all participant systems.

Event detection (ED), a key subtask of information extraction, aims to recognize instances of specific event types in text. Previous studies on the task have verified the effectiveness of integrating syntactic dependency into graph convolutional networks. However, these methods usually ignore dependency label information, which conveys rich and useful linguistic knowledge for ED. In this paper, we propose a novel architecture named Edge-Enhanced Graph Convolution Networks (EE-GCN), which simultaneously exploits syntactic structure and typed dependency label information to perform ED. Specifically, an edge-aware node update module is designed to generate expressive word representations by aggregating syntactically-connected words through specific dependency types. Furthermore, to fully explore clues hidden from dependency edges, a node-aware edge update module is introduced, which refines the relation representations with contextual information. These two modules are complementary to each other and work in a mutual promotion way. We conduct experiments on the widely used ACE2005 dataset and the results show significant improvement over competitive baseline methods.