Hyungjun Yoon
Ph.D. Candidate @ KAISTI am a Ph.D. candidate in Mobile Intelligence & Interaction Lab at KAIST, advised by Professor Sung-Ju Lee. I was a research intern at Nokia Bell Labs (Mentor Lorena Qendro, hosted by Fahim Kawsar), Microsoft Research (mentored and hosted by Professor Lili Qiu), and a visiting researcher at NTU (advised by Professor Mo Li). I do research on Foundation models and LLMs for Mobile Sensing and Healthcare applications. I enjoy exploring how the techniques can be used for real-world problems.
News
- Jul. 2026|🛫 ICML '26 @ Seoul, South Korea (Jul. 9 - Jul. 11)
- Jun. 2026|🛫 AHLI Health AI Summer Camp @ Seattle, USA (Jun. 22 - Jun. 28)
- May. 2026|🎓 Passed my Ph.D. Dissertation Defense (committee: Prof. Sung-Ju Lee, Prof. Edward Choi, Prof. Kimin Lee, Prof. Mo Li, Prof. Lili Qiu)
- May. 2026|🎉 Accepted to AHLI Health AI Summer Camp with full scholarship
- May. 2026|🎤 Invited talk at KAIST AI (host: Prof. Seong Joon Oh)
- May. 2026|👔 Organizer at WellComp 2026 @ UbiComp/ISWC '26
- Apr. 2026|🛫 ICLR '26 @ Rio de Janeiro, Brazil (Apr. 23 - Apr. 27)
- Apr. 2026|🎉 Paper accepted to ACL '26 (findings)
- Jan. 2026|🎉 Paper accepted to IEEE PacificVis '26
- Jan. 2026|🎉 Paper accepted to ICLR '26
- Dec. 2025|🛫 NeurIPS '25 @ San Diego, USA (Dec. 2 - Dec. 7)
- Nov. 2025|🏆 Selected as Winner of the Qualcomm Innovation Fellowship
- Nov. 2025|🎤 Invited talk at KAIST Mobile Computing Course
- Oct. 2025|🏆 Selected as Finalist of the Qualcomm Innovation Fellowship
- Sep. 2025|I am serving as the lab leader of Mobile Intelligence & Interaction Lab
- Jun. 2025|👨💻 Research internship at Nokia Bell Labs (Mentor Lorena Qendro)
- May. 2025|🛫 SenSys '25 @ Irvine, USA (May. 5 - May. 9)
- May. 2025|🎉 Paper accepted to MobiSys Workshop (EnvSys) '25
- Apr. 2025|🎉 Paper accepted to IEEE TMC '25
- Mar. 2025|🎤 Invited talk at UNIST (host: Prof. Taesik Gong)
- Feb. 2025|🎉 Paper accepted to SenSys '25
- Feb. 2025|🎉 Paper accepted to ACM CHI '25 EA
- Nov. 2024|🛫 EMNLP '24 @ Miami, USA (Nov. 12 - Nov. 16)
- Nov. 2024|🎤 Invited talk at MSRA
- Sep. 2024|🎉 Paper accepted to UbiComp '25
- Sep. 2024|🎉 Paper accepted to EMNLP '24 (main)
- Sep. 2024|👨💻 Research internship at Microsoft Research (Mentor Prof. Lili Qiu)
- Oct. 2023|🎉 Paper accepted to EMNLP '23 (main)
- Sep. 2022|Visiting researcher at NTU, Singapore (Advisor Prof. Mo Li) (by Dec. 2022)
- May. 2022|🛫 ACM CHI '22 @ New Orleans, USA (Apr. 30 - May. 5)
- Mar. 2022|🏆 Honorable Mention at ACM CHI '22
- Nov. 2021|🎉 Paper accepted to ACM CHI '22
- Mar. 2021|🎓 Started my Ph.D. in Mobile Intelligence & Interaction Lab
- Mar. 2020|🎓 Started my M.S. in Mobile Intelligence & Interaction Lab
- Feb. 2020|🎓 Graduated from KAIST as B.S. (Cum Laude)
Publications
Preprints
"Wearable Foundation Models Should Go Beyond Static Encoders"Yu Yvonne Wu*, Yuwei Zhang*, Hyungjun Yoon*, Ting Dang, Dimitris Spathis, Tong Xia, Qiang Yang, Jing Han, Dong Ma, Sung-Ju Lee, and Cecilia Mascolo (* Equal contribution)arXiv preprint pdf
arXiv
Conferences and Journals
"ConSensus: Multi-Agent Collaboration for Multimodal Sensing"Hyungjun Yoon, Mohammad Malekzadeh, Sung-Ju Lee, Fahim Kawsar, and Lorena QendroACL 2026 Findings pdf
arXiv
"Evaluating Visual Prompts with Eye-Tracking Data for MLLM–Based Human Activity Recognition"Jae Young Choi, Seon Gyeom Kim, Hyungjun Yoon, Taeckyung Lee, Donggun Lee, Jaeryung Chung, Jihyung Kil, Ryan Rossi, Sung-Ju Lee, and Tak Yeon LeeIEEE PacificVis 2026 pdf
"Beyond Hearing: Learning Task-agnostic ExG Representations from Earphones via Physiology-informed Tokenization"Hyungjun Yoon*, Seungjoo Lee*, Yu Wu*, Xiaomeng Chen*, Taiting Lu, Freddy Yifei Liu, Taeckyung Lee, Hyeongheon Cha, Haochen Zhao, Gaoteng Zhao, Dongyao Chen, Cecilia Mascolo, Sung-Ju Lee, and Lili Qiu (* Equal contribution)ICLR 2026 pdf
arXiv
"From Vision to Motion: Translating Large-Scale Knowledge for Data-Scarce IMU Applications"Hyungjun Yoon, Hyeongheon Cha, Canh Hoang Nguyen, Taesik Gong, and Sung-Ju LeeIEEE TMC 2025 (JCR '23 IF < 5%) pdf
website
"SelfReplay: Adapting Self-Supervised Sensory Models via Adaptive Meta-Task Replay"Hyungjun Yoon, Jaehyun Kwak, Biniyam Aschalew Tolera, Gaole Dai, Mo Li, Taesik Gong, Kimin Lee, and Sung-Ju LeeSenSys 2025 pdf
website
"ContrastSense: Domain-invariant Contrastive Learning for In-the-wild Wearable Sensing"Gaole Dai, Huatao Xu, Hyungjun Yoon, Sung-Ju Lee, Rui Tan, and Mo LiUbiComp 2025 pdf
website
"By My Eyes: Grounding Multimodal Large Language Models with Sensor Data via Visual Prompting"Hyungjun Yoon, Biniyam Aschalew Tolera, Taesik Gong, Kimin Lee, Sung-Ju LeeEMNLP 2024 Main pdf
website
Qualcomm Innovation Fellowship Winner
"FedTherapist: Mental Health Monitoring with User-Generated Linguistic Expressions on Smartphones via Federated Learning"Jaemin Shin, Hyungjun Yoon, Seungjoo Lee, Sungjoon Park, Yunxin Liu, Jinho D. Choi, and Sung-Ju LeeEMNLP 2023 Main pdf
website
"MyDJ: Sensing Food Intakes with an Attachable on Your Eyeglass Frame"Jaemin Shin, Seungjoo Lee, Taesik Gong, Hyungjun Yoon, Hyunchul Roh, Andrea Bianchi, and Sung-Ju LeeACM CHI 2022 pdf
website
video
Honorable Mention Award
Workshop Publications
"CrashSniffer: UWB-Based Anchor-Free Pedestrian Collision Prediction for Personal Mobility Vehicles"Taeckyung Lee, Juseung Lee, Ryuhaerang Choi, Seungjoo Lee, Hyeongheon Cha, Hyungjun Yoon, Song Min Kim, Sangwook Bak, and Sung-Ju LeeEnvSys 2025 (MobiSys Workshop) (Oral presentation, peer-reviewed, archived) pdf
website
""I know my personal data does not leave my phone, but ...": Understanding User (Mis)Perceptions of On-Device AI Voice Phishing Detection"Subin Park, Hyungjun Yoon, Janu Kim, Hyoungshick Kim, and Sung-Ju LeeACM CHI 2025 EA pdf
website
Archived Manuscripts
"Recover as It is Designed to Be: Recovering from Compatibility Mobile App Crashes by Reusing User Flows"Donghwi Kim, Hyungjun Yoon, Chang Min Park, Sujin Han, Youngjin Kwon, Steve Ko, and Sung-Ju LeearXiv preprint pdf
arXiv
Honors
For qualified papers in the field of AI/ML (Top 15), 2025
🏆 Best Paper Honorable Mention
ACM CHI 2022; Awarded for the top 5% of all submissions🏆 Dean's List
KAIST, Spring 2019; Awarded to the top 3% students in College of EngineeringEducation & Research Experience
Research internship, Microsoft Research, China (Mentor Prof. Lili Qiu)
Ph.D. in Electrical Engineering, KAIST, Republic of Korea (Advisor Prof. Sung-Ju Lee)
Visiting researcher at Wireless and Networked Distributed Sensing (WANDS) group, NTU, Singapore (Advisor Prof. Mo Li)
M.S. in Computer Science, KAIST, Republic of Korea (Advisor Prof. Sung-Ju Lee)
B.S. in Computer Science, KAIST, Republic of Korea (Cum Laude)
Patents
"UWB-Based Pedestrian Collision Avoidance System for Personal Mobility Devices"
Sung-Ju Lee, Hyeongheon Cha, Taeckyung Lee, Seungjoo Lee, Hyungjun YoonKorea Patent; Filing date: 2025.11.06, No. 10-2025-0166592"Adaptive State-Space Model-Based Deep Learning System for Real-Time Data Inference on Mobile Devices"
Sung-Ju Lee, Seungjoo Lee, Hyungjun YoonKorea Patent; Filing date: 2025.03.31, No.10-2025-0040898"Inference Method Using Dynamic Resource-Based Adaptive Deep Learning Model and Deep Learning Model Inference Device Performing Method"
Sung-Ju Lee, Donghwi Kim, Hyungjun Yoon, Yewon Kim, Sujin HanUS Patent; Filing date: 2023.12.20, No.18/389,848; Korea patent; Filing date: 2023.05.10, No.10-2023-0060780"A System of Mental Health Monitoring with User-Generated Linguistic Expressions on Smartphones via Federated Learning"
Sung-Ju Lee, Hyungjun Yoon, Seungjoo Lee, Jaemin ShinKorea Patent; Filing date: 2023.11.23, No.10-2023-0164077"Artificial Intelligence Model Training Method and Apparatus for Voice Phishing Detection"
Sung-Ju Lee, Seungjoo Lee, Hyungjun YoonKorea Patent; Filing date: 2023.10.04, No.10-2023-0131748"Dynamic Resource-Based Adaptive Smartphone On-Device Inference Method"
Sung-Ju Lee, Hyungjun Yoon, Donghwi Kim, Sujin Han, Yewon KimKorea Patent; Filing date: 2022.12.21, No.10-2022-0180842"Time-Aware Reinforcement-Learning Method for Geographic Ad Hoc Routing with Pre-defined Mobility and Computer Device for the Same"
Jaeha Ahn, Sung-Ju Lee, Taesik Gong, Hyungjun Yoon, Taeckyung LeeKorea Patent; Filing date: 2022.11.11, No.10-2022-0150662"Reinforcement Learning for Ad-hoc Routing Using Pre-defined Mobility"
Sung-Ju Lee, Taesik Gong, Hyungjun Yoon, Taeckyung Lee, Jaeha AhnKorea Patent; Filing date: 2022.03.21, No.10-2022-0034824