The invention discloses an archive
knowledge base construction and retrieval method and
system based on multi-
modal data fusion. The method comprises the steps that heterogeneous archive data are cleaned, image features are extracted through CNN, text features are extracted through Transform, audio is converted into text and then subjected to similarity, a unified
feature vector is generated, and
metadata is constructed according to archive code association; creating a
graph database instance, defining nodes and relationship types, importing entities and relationships, and storing feature vectors and
metadata; the features are mapped to a high-dimensional shared
semantic space, positive and
negative sample pairs are constructed to update embedded layer parameters, self-attention is used in modalities, a shared attention mechanism is used between modalities, weights are adjusted according to archive features, and unified knowledge representation is generated; segmenting the steering quantity of the multi-
modal data, storing the steering quantity into a
database, and adopting hierarchical indexing and optimizing as required; related document fragments are retrieved through RAG technology vectors, answers are generated with the help of a large
language model, and session feedback is provided. The file retrieval efficiency and accuracy are improved.