Minghang Liu

Author directory

2026

Cognitive Diagnosis Models (CDMs) play a pivotal role in personalized online learning. Traditional CDMs rely on discrete, ID-based embeddings to represent students, exercises, and concepts. This paradigm diverges from the nature of learner cognition, where knowledge is not stored and retrieved as isolated symbols. As a result, CDMs suffer from semantic limitations when new exercises or concepts appear. In this paper, we propose a Process-aware Language Cognitive Diagnosis (PLCD) framework that uses language-derived structures as cognitive priors and response records to calibrate student posterior states. PLCD leverages large language models (LLMs) to construct concept schemas and cognitive process graphs, and uses target-conditioned semantic memory to retrieve historical responses that are relevant to each target exercise. A process-grounded Language-to-Cognition Mapper with DA-MoE experts and process-level contrastive learning then maps the textual evidence into a unified cognitive space. Experimental results show that PLCD not only outperforms traditional baselines in predicting student performance but also exhibits strong cognitive transfer capabilities. These results connect the computational power of LLMs with the psychometric goal of measuring latent knowledge states, suggesting that structured language priors calibrated by response records can improve cold-start robustness and cognitive grounding.

2025

Multimodal Knowledge Graphs (MMKGs) enhance knowledge representations by integrating structural and multimodal information of entities. Recently, MMKGs have proven effective in tasks such as information retrieval, knowledge discovery, and question answering. Current methods typically utilize pre-trained visual encoders to extract features from images associated with each entity, emphasizing complex cross-modal interactions. However, these approaches often overlook the varying relevance of visual information across entities. Specifically, not all entities benefit from visual data, and not all associated images are pertinent, with irrelevant images introducing noise and potentially degrading model performance. To address these issues, we propose the Differentiated Vision for Multimodal Knowledge Graphs (DVMKG) model. DVMKG evaluates the necessity of visual modality for each entity based on its intrinsic attributes and assesses image quality through representativeness and diversity. Leveraging these metrics, DVMKG dynamically adjusts the influence of visual data during feature integration, tailoring it to the specific needs of different entity types. Extensive experiments on multiple benchmark datasets confirm the effectiveness of DVMKG, demonstrating significant improvements over existing methods.