A novel word sense disambiguation approach using WordNet knowledge graph

Selective UMLS knowledge infusion for biomedical question answering

One of the artificial intelligence applications in the biomedical field is knowledge-intensive question-answering. As domain expertise is particularly crucial in this field, we propose a method for efficiently infusing biomedical knowledge into pretrained language models, ultimately targeting biomedical question-answering. Transferring all semantics of a large knowledge graph into the entire model requires too many parameters, increasing computational cost and time. We investigate an efficient approach that leverages adapters to inject Unified Medical Language System knowledge into pretrained language models, and we question the need to use all semantics in the knowledge graph. This study focuses on strategies of partitioning knowledge graph and either discarding or merging some for more efficient pretraining. According to the results of three biomedical question answering finetuning datasets, the adapters pretrained on semantically partitioned group showed more efficient performance in terms of evaluation metrics, required parameters, and time. The results also show that discarding groups with fewer concepts is a better direction for small datasets, and merging these groups is better for large dataset. Furthermore, the metric results show a slight improvement, demonstrating that the adapter methodology is rather insensitive to the group formulation.

Investigation of features causing semantic mergers of English modal verbs by approach of attribute partial order diagram

Semantic merger, which is a phenomenon of semantic convergence of two meanings of a word in a certain context, is a kind of semantic indeterminacy in natural language, however, it brings trouble for natural language processing. Discovery of the features causing semantic mergers has been a significant but tough issue in natural language processing. Until now this issue has remained untouched. Therefore, in this article, this issue is studied. Based on a 1.8 million word English multi-genre corpus, taking English modal verb may as the target word, the contextual features causing semantic mergers between may(root possibility) and may(epistemic possibility) are investigated by an approach of attribute partial order diagram (APOD). First, the objects of may is categorized into 3 classes based on the idea of the three-way decision: may 1(root possibility), may 2(epistemic possibility) and may 3(merger), then the rules for word sense disambiguation (WSD) of the three classes are extracted, respectively, and a comparison is made among the rules for different classes, and finally the features causing semantic merger of may are discovered. The discovered knowledge provides valuable evidence for finding the semantic merger, the cause of the semantic merger and the solution of semantic mergers of may, and the proposed approach can also be use for other modal verbs, which may benefit the natural language processing of English modal verbs.