Abstract: [Purpose/Significance] The spirit of Yuhuatai martyrs is one of the important components of the new democratic revolutionary spirit of the Communist Party of China (CPC). The primary documents about Yuhuatai martyrs is the significant source to record their spirit. Using text processing technologies, such as content annotation and feature construction to deeply excavate the content of the documents, which is not only conducive to carrying forward revolutionary culture and continuing the red spirit, but also beneficial to expanding the application objects of technology and promoting the improvement of text mining technology. [Method/Process] In this paper, the original documents related to Yuhuatai martyrs were used as the data source, which include 12,329 original records in 8 types of documents, including biographies of martyrs, letters, diaries, interrogation materials of the enemy and puppet governments, trial records, and oral history. Then the lightweight ontology of Yuhuatai martyrs was built, which was used as the feature description framework of Yuhuatai martyrs. Based on the domain ontology and trigger word features, relevant instances in the ontology were extracted from the documents of Yuhuatai martyrs, and the formal features of the multi-dimensional attributes of Yuhuatai martyrs were constructed and described. The categories and attributes of lightweight ontology described the Yuhuatai martyrs' group feature framework. Through the data analysis of the extracted ontology instance, the data analysis of Yuhuatai martyr group feature can be realized. [Results/Conclusions] Through the statistical analysis of the basic information, revolutionary activities and the relevant text content of the struggle in prison of Yuhuatai martyrs, this paper further revealed the group characteristics from the perspective of data, including: high education level, sacrifice at a young age, long-term struggle in the ruling center of the Kuomintang, adherence to faith, loyalty to CPC, full of family and country feelings of peace and order, and conscious practice of noble moral pursuit. By the application of lightweight ontology and other quantitative analysis methods in this paper, it is helpful to visualize the lofty ideals and beliefs of Yuhuatai martyrs, noble moral sentiments and the dauntless spirit of sacrifice for the people. This paper has a certain reference value for the presentation and dissemination of innovative Yuhuatai martyrs' spirit.

Key words: revolution literature, Yuhuatai martyrs, group characteristics, lightweight ontology, content analysis