Joonghyuk Hahn

About Me

I am a PhD candidate in Computer Science with a dual focus on formal language theory and natural language processing (NLP). My research spans M-unambiguous language, language sparsity, and probability convergence, as well as advanced NLP techniques like self-training for few-shot learning and grammar-based data augmentation. I am set to graduate soon and have contributed to several publications in both theoretical computer science and NLP applications.

Research

My research interests include:

• M-equivalence, strong M-equivalence, and language sparsity
• Formal language theory and computational complexity
• Natural language processing (NLP) with a focus on few-shot learning and self-training techniques
• Grammar-based data augmentation and its application in text classification
• Parikh matrix mapping and its relevance to computational linguistics

Publications

• Hyunjoon Cheon, Joonghyuk Hahn, Yo-Sub Han (2024). On the Decidability of Infix Inclusion Problem. Theory of Computing Systems, Vol. 68, 301--321.
• Ingyu Baek, Joonghyuk Hahn, Yo-Sub Han, Kai Salomaa (2024). Universal Rewriting Rules for the Parikh Matrix Injectivity Problem. Proceedings of DLT'24, LNCS 14791, 68--81.
• Ju-Hyoung Lee, Joonghyuk Hahn, Hyeon-Tae Seo, Jiho Park, Yo-Sub Han (2024). SuperST: Superficial Self-Training for Few-Shot Text Classification. Proceedings of LREC-COLING 2024, 15436--15447.
• J.B. Kim, Hazel Kim, Joonghyuk Hahn, Yo-Sub Han (2023). ATHENA: Mathematical Reasoning with Thought Expansion. Proceedings of EMNLP 2023, 16315--16327.
• Joonghyuk Hahn, Hyunjoon Cheon, Elizabeth Grace Orwig, Su-Hyeon Kim, Sang-Ki Ko, Yo-Sub Han (2023). GDA: Grammar-based Data Augmentation for Text Classification using Slot Information. Findings of EMNLP 2023, 7291--7306.
• Joonghyuk Hahn, Hyunjoon Cheon, Yo-Sub Han (2023). M-equivalence of Parikh Matrix over a Ternary Alphabet. Proceedings of CIAA'23, LNCS 14151, 141--152.
• Jikyoeng Son, Joonghyuk Hahn, Hyeon-Tae Seo, Yo-Sub Han (2022). Boosting Code Summarization by Embedding Code Structures. Proceedings of COLING'22, 5966--5977.
• Hyunjoon Cheon, Joonghyuk Hahn, Yo-Sub Han (2022). On the Decidability of Infix Inclusion Problem. Proceedings of DLT'22, LNCS 13257, 115--126.
• Joonghyuk Hahn, Hyunjoon Cheon, Kyuyeol Han, Cheongjae Lee, Junseok Kim, Yo-Sub Han (2021). Self-Training using Rules of Grammar for Few-Shot NLU. Findings of EMNLP 2021, 4576--4581.
• Hyunjoon Cheon, Joonghyuk Hahn, Yo-Sub Han, Sang-Ki Ko (2021). Most Pseudo-copy Languages Are Not Context-free. Proceedings of COCOON'21, 189--200.

CV

You can download my CV here.

Contact

Email: greghahn@yonsei.ac.kr

DBLP: Joonghyuk Hahn

GitHub: github.com/peer0