Cheonbok Park

* Equal contribution · † Corresponding author

Conference, Journal, and Workshop Papers

2026

A Simple Unigram Cross-Entropy Lens on the Lexical Imprint of Pre-training Data
Jeonghoon Kim*, Woojin Chung*, Woomin Song, Cheonbok Park, Nako Sung, and Jinwoo Shin
Conference on Neural Information Processing Systems (NeurIPS), 2026. Accepted (Poster).
Paper

From Unverifiable Domain Text to Cross-Lingual RLVR via Code-Switched Task Synthesis
Cheonbok Park*, Jihwan Kim*, Shinyoung Joo, Joosung Lee, Hwiyeol Jo, Jeonghoon Kim, and Jaegul Choo
Empirical Methods in Natural Language Processing (EMNLP), 2026. Accepted.
Paper

What Models Know, How Well They Know It: Knowledge-Weighted Fine-Tuning for Learning When to Say “I Don’t Know”
Joosung Lee, Hwiyeol Jo, Donghyeon Ko, Kyubyung Chae, Cheonbok Park, and Jeonghoon Kim
Findings of the Association for Computational Linguistics: EMNLP, 2026. Accepted.
Paper

Enhancing Hallucination Detection via Future Context
Joosung Lee, Cheonbok Park, Hwiyeol Jo, Jeonghoon Kim, Joonsuk Park, and Kang Min Yoo
Findings of the Association for Computational Linguistics: ACL, 2026.
Paper

Sommelier: Scalable Open Multi-turn Audio Pre-processing for Full-duplex Speech Language Models
Kyudan Jung, Jihwan Kim, Soyoon Kim, Jeonghoon Kim, Jaegul Choo, and Cheonbok Park^†
Annual Meeting of the Association for Computational Linguistics (ACL), Industry Track, 2026.
Paper

2025

Code-Switching Curriculum Learning for Multilingual Transfer in LLMs
Haneul Yoo, Cheonbok Park, Sangdoo Yun, Alice Oh, and Hwaran Lee
Findings of the Association for Computational Linguistics: ACL, 2025.
Paper

Peri-LN: Revisiting Normalization Layer in the Transformer Architecture
Jeonghoon Kim, Byeongchan Lee, Cheonbok Park, Yeontaek Oh, Beomjun Kim, Taehwan Yoo, Seongjin Shin, Dongyoon Han, Jinwoo Shin, and Kang Min Yoo
International Conference on Machine Learning (ICML), 2025.
Paper

KMMLU: Measuring Massive Multitask Language Understanding in Korean
Guijin Son, Hanwool Lee, Sungdong Kim, Seungone Kim, Niklas Muennighoff, Taekyoon Choi, Cheonbok Park, Kang Min Yoo, and Stella Biderman
Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics (NAACL), Long Paper, 2025.
Paper

2024

Aligning Language Models to Explicitly Handle Ambiguity
Hyuhng Joon Kim, Youna Kim, Cheonbok Park, Junyeob Kim, Choonghyun Park, Kang Min Yoo, Sang-goo Lee, and Taeuk Kim
Empirical Methods in Natural Language Processing (EMNLP), 2024.
Paper

Adaptive Contrastive Decoding in Retrieval-Augmented Generation for Handling Noisy Contexts
Youna Kim, Hyuhng Joon Kim, Cheonbok Park, Choonghyun Park, Hyunsoo Cho, Junyeob Kim, Kang Min Yoo, Sang-goo Lee, and Taeuk Kim
Findings of the Association for Computational Linguistics: EMNLP, 2024.
Paper

Mitigating Semantic Leakage in Cross-lingual Embeddings via Orthogonality Constraint
Dayeon Ki, Cheonbok Park, and Hyunjoong Kim
Workshop on Representation Learning for NLP (RepL4NLP), 2024.
Paper

2023

Towards Accurate Translation via Semantically Appropriate Application of Lexical Constraints
Yujin Baek*, Koanho Lee*, Dayeon Ki, Cheonbok Park, Hyoung-Gyu Lee, and Jaegul Choo (*: equal contributions)
Annual Meeting of the Association for Computational Linguistics (ACL), Findings of ACL, 2023.
Paper

PePe: Personalized Post-editing Model utilizing User-generated Post-edits
Jihyeon Lee*, TaeHee Kim*, Yunwon Tae*, Cheonbok Park, and Jaegul Choo (*: equal contributions)
Conference of the European Chapter of the Association for Computational Linguistics (EACL), Findings of EACL, 2023.
Paper

A Visual Analytics System for Improving Attention-based Traffic Forecasting Models
Seungmin Jin, Hyunwook Lee, Cheonbok Park, Hyeshin Chu, Yunwon Tae, Jaegul Choo, and Sungahn Ko
IEEE Trans. on Visualization and Computer Graphics (TVCG), 2023 (Proc. IEEE VIS’22)
Paper

2022

Specializing Multi-domain NMT via Penalizing Low Mutual Information
Jiyoung Lee, Hantae Kim, Hyunchang Cho, Edward Choi, and Cheonbok Park^†
Empirical Methods in Natural Language Processing (EMNLP), Short Paper, 2022
Paper

Residual Correction in Real-Time Traffic Forecasting
Daejin Kim*, Youngin Cho*, Dongmin Kim, Cheonbok Park, and Jaegul Choo (*: equal contributions)
ACM International Conference on Information and Knowledge Management (CIKM), 2022.
Paper

DaLC: Domain Adaptation Learning Curve Prediction for Neural Machine Translation
Cheonbok Park, Hantae Kim, Ioan Calapodescu, Hyun Chang Cho, and Vassilina Nikoulina
Meeting of the Association for Computational Linguistics (ACL), Findings Long Paper, 2022
Paper

Reversible Instance Normalization for Accurate Time-Series Forecasting against Distribution Shift
Taesung Kim*, Jinhee Kim*, Yunwon Tae, Cheonbok Park, Jang-Ho Choi, and Jaegul Choo (*: equal contributions)
International Conference on Learning Representations (ICLR), 2022.
Paper

PASTA: PArallel Spatio-Temporal Attention with Spatial Auto-Correlation Gating for Fine-Grained Crowd Flow Prediction
Chung Park, Junui Hong, Cheonbok Park, Taesan Kim, Minsung Choi, and Jaegul Choo
Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD), 2022.
Paper

2021

Unsupervised Neural Machine Translation for Low-Resource Domains via Meta-Learning
Cheonbok Park*, Yunwon Tae*, TaeHee Kim, Soyoung Yang, Mohammad Azam Khan, Lucy Park and Jaegul Choo (* indicates equal contribution)
Meeting of the Association for Computational Linguistics (ACL), Long Paper, 2021
Paper

VATUN: Visual Analytics for Testing and Understanding Convolutional Neural Networks
Cheonbok Park*, Soyoung Yang*, Inyoup Na*, Sunghyo Chung, Sungbok Shin, Bum Chul Kwon, Deokgun Park, and Jaegul Choo (* indicates equal contribution)
EG/VGTC Conference on Visualization (EuroVis), Short Paper, 2021
Paper

An Empirical Experiment on Deep Learning Models for Predicting Traffic Data
Hyunwook Lee, Cheonbok Park, Seungmin Jin, Hyeshin Chu, Jaegul Choo, and Sungahn Ko
IEEE International Conference on Data Engineering (ICDE), Short Paper, 2021.
Paper

2020

ST-GRAT: A Novel Spatio-temporal Graph Attention Networks for Accurately Forecasting Dynamically Changing Road Speed
Cheonbok Park, Chunggi Lee, Hyojin Bahng, Yunwon Tae, Seungmin Jin, Kihwan Kim, Sungahn Ko, and Jaegul Choo
ACM International Conference on Information and Knowledge Management (CIKM), 2020
Paper

2019

SANVis: Visual Analytics for Understanding Self-Attention Networks
Cheonbok Park, Inyoup Na, Yongjang Jo, Sungbok Shin, Jaehyo Yoo, Bum Chul Kwon, Jian Zhao, Hyungjong Noh, Yeonsoo Lee, and Jaegul Choo
IEEE VIS, Short Paper, 2019, Vancouver, Canada.
Paper

AILA: Attentive Interactive Labeling Assistant for Document Classification through Attention-based Deep Neural Networks
Minsuk Choi, Cheonbok Park, Soyoung Yang, Yonggyu Kim, Jaegul Choo, and Sungsoo (Ray) Hong
ACM CHI Conference on Human Factors in Computing Systems (CHI), 2019, Glasgow, UK.
Paper

A Comparison of the Effects of Data Imputation Methods on Model Performance
Wooyoung Kim*, Wonwoong Cho*, Jangho Choi, Jiyong Kim, Cheonbok Park, Jaegul Choo (* indicates equal contribution)
IEEE International Conference on Advanced Communications Technology (ICACT), 2019, Pyeongchang, KR.
Paper

2017

Real-time UAV sound detection and analysis system
Juhyun Kim, Cheonbok Park, Jinwoo Ahn, Youlim Ko, Junghyun Park, John C. Gallagher
IEEE Sensors Applications Symposium (SAS), 2017, Glassboro, NJ, USA.
Paper

2016

ReVACNN: Steering Convolutional Neural Network via Real-Time Visual Analytics
Sunghyo Chung, Cheonbok Park, Sangho Suh, Kyeongpil Kang, Jaegul Choo, and Bum Chul Kwon
NIPS Workshop on the Future of Interactive Machine Learning (FILM), 2016.
Program

ReVACNN: Real-Time Visual Analytics for Convolutional Neural Network
Sunghyo Chung, Sangho Suh, Cheonbok Park, Kyeongpil Kang, Jaegul Choo, and Bum Chul Kwon
ACM SIGKDD Workshop on Interactive Data Exploration and Analytics (KDD-IDEA), 2016, San Francisco, CA.
Paper

Preprints

When Verifiable Rewards Switch the Language: Cross-Lingual Collapse in Chain-of-Thought
Cheonbok Park*, Jeonghoon Kim*, Joosung Lee, Sanghwan Bae, Jaegul Choo, and Kang Min Yoo
arXiv preprint, 2025 (revised February 2026).
Paper

ReGUIDE: Data Efficient GUI Grounding via Spatial Reasoning and Search
Hyunseok Lee, Jeonghoon Kim, Beomjun Kim, Jihoon Tack, Chansong Jo, Jaehong Lee, Cheonbok Park, Sookyo In, Jinwoo Shin, and Kang Min Yoo
arXiv preprint, 2025.
Paper

Technical Reports

HyperCLOVA X 32B Think
NAVER Cloud HyperCLOVA X Team (including Cheonbok Park)
Technical report, 2026.
Paper

HyperCLOVA X 8B Omni
NAVER Cloud HyperCLOVA X Team (including Cheonbok Park)
Technical report, 2026.
Paper

HyperCLOVA X THINK Technical Report
NAVER Cloud HyperCLOVA X Team (including Cheonbok Park)
Technical report, 2025.
Paper

HyperCLOVA X Technical Report
Kang Min Yoo et al. (including Cheonbok Park)
Technical report, 2024.
Paper