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Short Biography

Yichi Zhang is a second-year Informatics Ph.D. student at The Pennsylvania State University advised by Dr. Yuchen Yang. Previously, he received his B.E. in Information Engineering from Zhejiang University.

His research interests include X of Y, where

• X = {Security, System, Theory, ...}
• Y = {Machine Learning, Language Model, ...}

Seeking research internships for Summer 2027.

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News

• 07/2026: One paper is accepted by TIFS 🎉🎉🎉.
• 05/2026: One paper is accepted by USENIX Security 2026 🎉🎉🎉.
• 05/2026: One paper is accepted by ICML 2026 🎉🎉🎉.
• 07/2025: One paper is accepted by ECAI 2025 🎉🎉🎉.
• 04/2025: Accepted by Informatics Ph.D. program of Penn State.

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Contact

Email: X @ Y, where

• X = {yichi.zhang.cs}, Y = {gmail.com}
• X = {yichi.zhang}, Y = {psu.edu}
• X = {ymz5721}, Y = {psu.edu}
• X = {yichics02}, Y = {gmail.com}
• X = {yichizhang}, Y = {zju.edu.cn}

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Publications

2026

• Xi Chen, Rui Zeng, Chunyi Zhou, Yichi Zhang, Yuwen Pu, Qingming Li, Lu Zhou, Zhe Liu, Shouling Ji. "PREFed: An Effective and Stealthy Static-Anchor Backdoor Attack via Trigger Pre-Optimization in Federated Learning". IEEE Transactions on Information Forensics and Security (TIFS), 2026.

• Yichi Zhang, Zhiqi Wang, Huan Zhang, Yuchen Yang. "HijackKV: New Threat in Position-Independent KV Cache Reuse". In Proceedings of the 35th USENIX Security Symposium, 2026.

• Cheng-Yi Lee, Yichi Zhang, Yuchen Yang, Chun-Shien Lu, Jun-Cheng Chen. "Rethinking Forgery Attacks on Semantic Watermarks in Black-Box Settings: A Geometric Distortion Perspective". In Proceedings of the 43rd International Conference on Machine Learning (ICML), 2026.

2025

• Yichi Zhang, Xiaogang Xu. "Diffusion Noise Feature: Accurate and Fast Generated Image Detection". In Proceedings of the 28th European Conference on Artificial Intelligence (ECAI), 2025.

Preprints

• Yichi Zhang, Qianqian Yang. "Efficient Implicit Neural Compression of Point Clouds via Learnable Activation in Latent Space". arXiv preprint arXiv:2504.14471, 2025.

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Service

Reviewer

• International Conference on Machine Learning (ICML), 2026.
• AAAI Conference on Artificial Intelligence (AAAI), 2026-2027.

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Awards and Grants

• USENIX Security Student Travel Grant, 2026.
• Academic Scholarship, Zhejiang University, 2022.

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