journal article·2025-11-26Open access

KA-RAG: Integrating Knowledge Graphs and Agentic Retrieval-Augmented Generation for an Intelligent Educational Question-Answering Model

Fangqun Gao, Shu Xu, Weiyan Hao, Tao Lu

Applied Sciences· Volume 15· Issue 23

Abstract

Generative artificial intelligence (AI) and large language models (LLMs) are reshaping the landscape of intelligent educational systems; however, existing solutions often suffer from unstructured resource organization, limited interpretability, and suboptimal retrieval precision. To address these challenges, this study introduces KA-RAG, a course-oriented question answering (QA) framework that integrates a structured Knowledge Graph (KG) with an Agentic Retrieval-Augmented Generation (Agentic-RAG) workflow. The system incorporates a responsive interface, a unified agent controller (ToolPlanner), a course knowledge graph, and a vector-based retrieval subsystem. By combining symbolic graph reasoning with dense semantic retrieval, the proposed dual-retrieval strategy supports interpretable, context-aware responses to course-related queries. Experiments conducted on a graduate-level Pattern Recognition course demonstrate that KA-RAG achieves a retrieval accuracy of 91.4%, semantic consistency of 87.6%, and an average response latency of 2.8 s. User surveys further reveal significant improvements in learning efficiency and satisfaction. The results validate the feasibility of integrating KG and Agentic-RAG techniques for knowledge-grounded educational applications, offering a practical pathway toward intelligent knowledge organization and interactive learning support.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Topic Modeling · Intelligent Tutoring Systems and Adaptive Learning · Advanced Graph Neural Networks

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Hubei Key Laboratory of Intelligent Robot, School of Computer Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, China

Library, Wuhan Institute of Technology, Wuhan 430205, China

Funding

the National Natural Science Foundation of China · Academic Project of Hubei Provincial Library Society · Central Government Guides Local Science and Technology Development Special Projects · the National Natural Science Foundation of Hubei · Enterprise Technology Innovation Project · Academic Project of Wuhan Institute of Technolog

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