I am a PhD student in Computer Science at Texas A&M University, advised by Ricardo Gutierrez-Osuna. Previously, I received my B.A. in Computer Science and Mathematics from Bucknell University, where I worked with Rajesh Kumar.

I am interested in human-computer interaction (HCI) and AI for healthcare. My current research focuses on wearable health sensing: I am developing methods to measure arterial blood flow with a quad-sensor TAG system worn on the wrist, which captures how the artery dilates as each pulse of blood passes through.

During my undergraduate studies, I worked on biometric technologies and trustworthy AI: (1) understanding how generative models threaten biometric systems and how to defend against them, and (2) using behavioral signals such as keystroke dynamics to detect LLM-assisted writing.

Before starting my PhD, I was a Robotics AI Engineer at Viettel Institute of Strategic Industrial Technology (Summer 2026), where I built an on-device Vietnamese speech recognition and LiDAR–camera perception pipeline for a quadruped robot. I was also an AI Research Intern at Knovel Engineering (2025–2026), working on chain-of-thought reasoning for medical visual question answering.


Recent Highlights 🔥
  • Aug 2026: Started my PhD in Computer Science at Texas A&M University!
  • Detecting LLM-Assisted Vietnamese Writing via Keystrokes accepted at ICTAI 2026! Check out the paper.

Selected Publications

* denotes equal contribution

ICTAI 2026
Detecting LLM-Assisted Vietnamese Writing via Keystrokes under Behavioral Manipulation
Thanh Dong*, An Ngo*, Minh Dau, Rajesh Kumar
Summary

We introduce a Vietnamese keystroke dataset covering bona fide composition, transcription, and paraphrasing, and a threat model in which users deliberately alter their typing to evade detection. Sequential models outperform feature-based approaches, and adversarial training with manipulated data improves robustness.

IJCB 2025
LLM-Assisted Cheating Detection in Korean Language via Keystrokes
Dong Hyun Roh, Rajesh Kumar, An Ngo
Summary

We propose interpretable keystroke features (pauses, bursts, timing irregularities) to detect LLM-assisted writing in Korean across cognitive levels of Bloom's taxonomy, reaching 85%+ accuracy on 69 users while remaining explainable.

IJCB 2024 Poster
Deep Generative Attacks and Countermeasures for Data-Driven Offline Signature Verification
An Ngo, Rajesh Kumar, Phuong Cao
Summary

We show that signatures forged by conditional GANs and VAEs raise the false acceptance rate of signature verification models from 3% to 25%, introduce an SSIM-based metric that explains attack success, and use adversarial training to bring attack success back under 3%.


Selected Preprints

Under Review
S-Chain: Structured Visual Chain-of-Thought for Medicine
Khai Le-Duc, Duy M. H. Nguyen, Phuong T. H. Trinh, Tien-Phat Nguyen, Nghiem T. Diep, An Ngo, Tung Vu, Trinh Vuong, Anh-Tien Nguyen, Mau Nguyen, Van Trung Hoang, Khai-Nguyen Nguyen, Hy Nguyen, Chris Ngo, Anji Liu, Nhat Ho, Anne-Christin Hauschild, Khanh Xuan Nguyen, Thanh Nguyen-Tang, Pengtao Xie, Daniel Sonntag, James Zou, Mathias Niepert, Anh Totti Nguyen
Summary

We present S-Chain, a medical dataset for structured visual chain-of-thought reasoning. Training medical vision-language models on S-Chain improves both their accuracy and explainability.


Earlier Work

  • Y. T. T. Hai, A. Ngo, N. Q. Dat, V. K. Solanki. Multi-input LSTM for water level forecasting in Black River at the border of Vietnam–China. ICMLANT 2021.
  • A. Ngo, N. N. Minh, N. Q. Dat, V. K. Solanki. Hybrid model Seasonal ARIMA-LSTM for prediction water level in Black River on the border Vietnam–China. Computational Intelligence in Machine Learning: Select Proceedings of ICCIML 2021.