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Mingkang Zhu

9 accepted papers

2026

Stratified GRPO: Handling Structural Heterogeneity in Reinforcement Learning of LLM Search Agents

ICML 2026poster

Large language model (LLM) agents increasingly rely on external tools such as search engines to solve complex, multi-step problems, yet their rollouts are structurally heterogeneous: variations in tool-call number, placement, and outcomes induce distinct behaviors and reward distributions. As a resu…

Cited by 5SourceScholar
2026

ViSurf: Visual Supervised-and-Reinforcement Fine-Tuning for Large Vision-and-Language Models

ICML 2026poster

Post-training Large Vision-and-Language Models (LVLMs) typically involves Supervised Fine-Tuning (SFT) for knowledge injection or Reinforcement Learning with Verifiable Rewards (RLVR) for performance enhancement. However, SFT often leads to sub-optimal performance, while RLVR remains constrained by …

Cited by 0SourceScholar
2026

VisionLeaf: Entropy-Guided Leaf-First Reasoning for Efficient and Accurate Think-with-Image

CVPR 2026

The "think-with-image" paradigm has recently gained traction for complex visual reasoning tasks. However, existing approaches often struggle with inference inefficiency due to a fixed number of redundant reasoning steps, as well as training instability. This challenge primarily arises from the direc

Cited by 0SourceScholar
2025

Enhancing LLM Knowledge Learning through Generalization

EMNLP 2025

As Large language models (LLMs) are increasingly deployed in diverse applications, faithfully integrating evolving factual knowledge into these models remains a critical challenge. Continued pre-training on paraphrased data has shown empirical promise for enhancing knowledge acquisition. However, th

2025

MiCo: Multi-image Contrast for Reinforcement Visual Reasoning

NeurIPS 2025poster

This work explores enabling Chain-of-Thought (CoT) reasoning to link visual cues across multiple images. A straightforward solution is to adapt rule-based reinforcement learning for Vision-Language Models (VLMs). However, such methods typically rely on manually curated question-answer pairs, which c…

Cited by 0SourceScholar
2025

TGDPO: Harnessing Token-Level Reward Guidance for Enhancing Direct Preference Optimization

ICML 2025poster

Recent advancements in reinforcement learning from human feedback have shown that utilizing fine-grained token-level reward models can substantially enhance the performance of Proximal Policy Optimization (PPO) in aligning large language models. However, it is challenging to leverage such token-leve…

2024

LogoSticker: Inserting Logos into Diffusion Models for Customized Generation

ECCV 2024poster

"Recent advances in text-to-image model customization have underscored the importance of integrating new concepts with a few examples. Yet, these progresses are largely confined to widely recognized subjects, which can be learned with relative ease through models’ adequate shared prior knowledge. In…

2023

Learning to Generalize Provably in Learning to Optimize

AISTATS 2023poster

Learning to optimize (L2O) has gained increasing popularity, which automates the design of optimizers by data-driven approaches. However, current L2O methods often suffer from poor generalization performance in at least two folds: (i) applying the L2O-learned optimizer to unseen optimizees, in terms…

2021

Sparse and Imperceptible Adversarial Attack via a Homotopy Algorithm

ICML 2021oral

Sparse adversarial attacks can fool deep neural networks (DNNs) by only perturbing a few pixels (regularized by $\ell_0$ norm). Recent efforts combine it with another $\ell_\infty$ imperceptible on the perturbation magnitudes. The resultant sparse and imperceptible attacks are practically relevant,…