Zirui Liao

Author directory

2026

Knowledge-based visual question answering (KB-VQA) requires vision-language models to understand images and use external knowledge, especially for rare entities and long-tail facts. Most existing retrieval-augmented generation (RAG) methods adopt a fixed pipeline that sequentially retrieves information, filters it, and then produces an answer. Such a design makes it difficult to adapt to diverse question types. Moreover, it separates retrieval from reasoning, making it hard for the model to decide when to search, how to refine queries, or when to stop. As a result, the retrieved evidence is often poorly aligned with the question. To address these limitations, we reformulate KB-VQA as a search-agent problem and model the solving process as a multi-step decision-making procedure. At each step, the agent selects one of four actions-Answer, Image Retrieval, Text Retrieval, and Caption-based on its current information state. We further design an automated pipeline to collect multi-step trajectories that record the agent’s reasoning process, tool usage, and intermediate decisions. These trajectories are then used as supervision for fine-tuning. Experiments on InfoSeek and E-VQA demonstrate that our method achieves state-of-the-art performance, consistently outperforming prior baselines and confirming the effectiveness of our framework.
In the unsupervised self-evolution of Multimodal Large Language Models, the quality of feedback signals during post-training is pivotal for stable and effective learning. However, existing self-evolution methods predominantly rely on majority voting to select the most frequent output as the pseudo-golden answer, which may stem from the model’s intrinsic biases rather than guaranteeing the objective correctness of the reasoning paths. To counteract the degradation, we propose Continuous Softened Retracing reSampling (CSRS) in MLLM self-evolution. Specifically, we introduce a Retracing Re-inference Mechanism (RRM) that the model re-inferences from anchor points to expand the exploration of long-tail reasoning paths. Simultaneously, we propose Softened Frequency Reward (SFR), which replaces binary rewards with continuous signals, calibrating reward based on the answers’ frequency across sampled reasoning sets. Furthermore, incorporated with Visual Semantic Perturbation (VSP), CSRS ensures the model prioritizes mathematical logic over visual superficiality. Experimental results demonstrate that CSRS significantly enhances the reasoning performance of Qwen2.5-VL-7B on benchmarks such as MathVision. We achieve state-of-the-art (SOTA) results in unsupervised self-evolution on geometric tasks.
Large Language Models (LLMs) serving as long-term personal companions require memory systems that support complex reasoning over extended dialogues. However, existing Retrieval-Augmented Generation (RAG) frameworks treat memory as passive storage, suffering from semantic collapse—where subjective beliefs and objective facts become indistinguishable—and rigid navigation that fails to connect dispersed information. We introduce CogMem, a cognitive memory architecture that reconstructs dialogue context through explicit structure. CogMem organizes memory via the PEC²F (Person-Event-Concept-Claim-Fact) schema, using dedicated Claim nodes to separate subjective attributions from objective records and prevent information contamination. Rather than static retrieval, CogMem employs a deterministic controller with four cognitive operators (anchoring, traversal, intersection, evidence grounding) that dynamically navigate the graph based on query intent. Comprehensive evaluation on LoCoMo and LongMemEval shows that CogMem achieves state-of-the-art performance across all task categories, surpassing neural memory systems and graph retrieval methods. These results demonstrate that structured cognitive modeling significantly improves long-term memory accuracy and robustness compared to passive vector retrieval.