Jiheon Choi

Bio

I received a B.S. degree in Software and Computer Engineering from Ajou University in Suwon, South Korea in August 2023. I am currently a Ph.D. student in the Department of Artificial Intelligence at Ajou University. I am a security-focused AI researcher and software engineer with 5+ years of experience spanning academic research and industry applications. I specialize in optimizing high-performance computing systems, developing secure distributed machine learning architectures, and implementing scalable cloud-based solutions. I am a member of the WISE (Web Infrastructure and Software Enhancement) Lab, led by Ph.D. Sangyoon Oh. My research interests include high-performance computing, distributed systems, and application security. You can contact me via email at unidev@ajou.ac.kr.

Research Interests

My research interests include, but not limited to the following areas.

High-Performance & Distributed Computing: HPC System Configuration and Job Scheduling
AI & Machine Learning: Distributed ML Architecture (i.e., Distributed LLM and GNN), Federated Learning and Privacy-Preserving ML Techniques, Machine Learning for Resource Optimization
Security & Privacy: Differential Privacy and Homomorphic Encryption, Automatic Security Vulnerability Assessment, Source ML System

Publications

Most recent publications on Google Scholar.
^‡ indicates equal contribution.

Selected
All

Scalability of Vector Indexing Methods for Large Language Model RAG Systems

Jiheon Choi, Sangyoon Oh

Korean Institute of Communications and Information Sciences Winter Conference 2025

Paper

When HPC Scheduling Meets Active Learning: Maximizing The Performance with Minimal Data

Jiheon Choi, Jaehyun Lee, Minsol Choo, Taeyoung Yoon, Oh-Kyoung Kwon, Sangyoon Oh

HPCAsia 2025: High Performance Computing in Asia-Pacific Region

Paper

Staleness Aware Semi-asynchronous Federated Learning

Miri Yu, Jiheon Choi, Jaehyun Lee, Sangyoon Oh

Journal of Parallel and Distributed Computing (JPDC) (IF: 3.4, JCR Q1)

Paper

Scalability of Vector Indexing Methods for Large Language Model RAG Systems

Jiheon Choi, Sangyoon Oh

Korean Institute of Communications and Information Sciences Winter Conference 2025

Paper

When HPC Scheduling Meets Active Learning: Maximizing The Performance with Minimal Data

Jiheon Choi, Jaehyun Lee, Minsol Choo, Taeyoung Yoon, Oh-Kyoung Kwon, Sangyoon Oh

HPCAsia 2025: High Performance Computing in Asia-Pacific Region

Paper

Staleness Aware Semi-asynchronous Federated Learning

Miri Yu, Jiheon Choi, Jaehyun Lee, Sangyoon Oh

Journal of Parallel and Distributed Computing (JPDC) (IF: 3.4, JCR Q1)

Paper

Job Application Prediction Consideration of Data Imbalance Problem in HPC

Taeyoung Yoon, Jiheon Choi, Oh-kyoung Kwon, Sangyoon Oh

KSC 2024: Korea Software Congress (KSC)

Paper

Streaming-Based High-Performance File Merging Scheme

Minseo Lee, Jiheon Choi, Taeyoung Yoon, Sangyoon Oh

KSC 2024: Korea Software Congress (KSC)

Paper

Dynamic Programming-Based Multilevel Graph Partitioning for Large-Scale Graph Data

Sergio P. Caetano, Miri Yu, Jiheon Choi, Sangyoon Oh

Korean Institute of Communications and Information Sciences Winter Conference 2024

Paper

Conditional LSTM-VAE-based Data Augmentation for Disaster Classification Prediction

Hyunsuk Jung, Jiheon Choi, Jongwon Park, Sehee Baek, Sangyoon Oh

The 9th International Conference on Next Generation Computing (ICNGC 2023)

Paper

MLOps Architecture for Fire Detection System

Hyunsuk Jung, Jiheon Choi, Jongwon Park, Sehee Baek, Sangyoon Oh

Spring Conference of the Korean Society for Next Generation Computing 2023

Paper

Analysis on Security Vulnerability in Federated Learning

Jiheon Choi, Miri Yu, Daegun Yoon, Sangyoon Oh

Korean Institute of Communications and Information Sciences Winter Conference 2023

Paper

A Data Service Architecture for Autonomous Driving Data Management

Jiheon Choi, Bongsub Song, Sangyoon Oh

Korean Institute of Communications and Information Sciences Summer Conference 2022

Paper

A method of analyzing web vulnerabilities using browser extension programs

Joonyoung Jeong, Dohun Koo, Jongmin Kim, Joowon Kim, Joomyeong Lee, Sanghyeon Lee, Gangseok Lee, Jiheon Choi

Conference on Information Security and Cryptography Winter 2021

Paper

A method to implement malware analysis ecosystem based on network

Jiheon Choi

Conference on Information Security and Cryptography Winter 2019

Paper

Patents

Jiheon Choi and Sangyoon Oh. "Method and Apparatus for Classifying Workload Using Artificial Intelligence Model" South Korea 10-2023-0029398 (Applied)
Jiheon Choi and Sangyoon Oh. "Apparatus and Method for Hotspot Prevention Based on Bloom Filter in Distributed Database Management System" South Korea 10-2024-0162896 (Applied)
Jiheon Choi et al. "System and Method for Detecting Dynamic Web Vulnerability of Data Normalization of HTTP Headers for Classification of HTTP Headers" South Korea 10-2024-0159333 (Applied)
Jiheon Choi et al. "Method for Automatic Diagnosis Vulnerability of Web and Apparatus for Performing The Method" South Korea 10-2311119 (Registered)
Jiheon Choi et al. "System and Method for Analyzing Akumalicious Code Based on Blockchain" South Korea 10-222804 (Registered)

Research Projects

A Study on Graph Parallel Processing Algorithm Based on GPU, funded by KISTI (Korea Institute of Science and Technology Information), National Research Council of Science and Technology (June 2024 - now)
Development of multi-tiered, multi-purpose autotuning framework for exa-scale supercomputers, funded by Ministry of Science and ICT (Nov 2023 - now)
Development of High Efficiency HPC Job Scheduling Algorithm, funded by Samsung Display Inc. (Jan 2024 - Feb 2025)
Development of Safety of the intended functionality from insufficiency of perception and decision making, funded by Korea Automotive Technology Institute (Sep 2022 - now)
AI Application Technology with MR-IoT Convergence to countermeasure Disasters, funded by Institute for Information & communication Technology Planning & evaluation (IITP) (Jan 2023 - Dec 2023)
User Engagement in Social/Mobile Platforms and Its Welfare Value, funded by Ajou University (Jan 2022 - Oct 2022)
Development of Web Application Vulnerability Assessment Software, funded by Ajou University (Jan 2022 - Oct 2022)
Development of Web Application Vulnerability Assessment Software, funded by Ministry of SMEs and Startups (Apr 2022 - Dec 2022)

Teaching Experience

Teaching Assistant, Ajou University (Jan 2022 -)
- Spring 2024, SCE 204: Object-oriented Programming
- Fall 2023, Fall 2024, SCE 338: Web System Design
- Fall 2022, Spring 2023, AAI 432: Artificial Intelligence Convergence Capstone Design
- Spring 2022, EBZ 3310: Data Analytics–Machine Learning
  - Responsible for designing the entire course with professor, creating course materials such as lecture notes, midterm exams, and assignments, and also assisting with grading tasks.
Mentor, Team Sparta Inc. (Jul 2022 - May 2023)
- Developer Bootcamp Mentoring (React, Node.js)
Mentor, Korea Open Source Software Association (Oct 2020 - now)
- Provided mentoring for the Open Source Software Developer Competition hosted by the Ministry of Science and ICT.
Coach, Elice Inc. (Nov 2021 - Aug 2022)
- Developer Bootcamp Mentoring (React, Node.js)
Instructor, Korea Information Technology Research Institute (Aug 2021 - Dec 2021)
- Led lectures on web, mobile, and system hacking, imparting advanced techniques and ethical hacking best practices to participants.
- The Cyber Guardians program is designed for high school students who wish to begin learning about the field of information security.

Vitæ

Full CV in PDF.

Ajou University Sep 2023 - now

Ph.D. student
Artificial Intelligence
Ajou University Jan 2022 - Aug 2023

Undergraduate Research Assistant
Distributed & Parallel Computing Lab
MONTHLY HACKING Inc. Aug 2020 - Dec 2022

Senior Research Engineer (Security & Software)
R&D Division
WAPAS SYSTEMS Inc. Oct 2019 - May 2020

Senior Researcher
Mobile Security R&D
Ajou University Mar 2019 - Aug 2023

B.S. degree
Software and Computer Engineering