First, from the content of the paper, the author can extract keywords from the topic and the paper.
1, taken from the title of the paper.
The title of a scientific paper contains the main information points of the paper, such as the research object and research methods. Therefore, the selection of keywords should first consider the selection from the title.
Step 2 extract from the newspaper
When extracting keywords, we can analyze the theme of the literature, find out the theme concept and central content of the paper, and extract words and phrases consistent with the theme concept from the title, abstract, hierarchical title and important paragraphs of the text as much as possible, so as to extract the keywords of the paper.
Secondly, from the application of words, the author can extract keywords from changing concepts and applying vocabulary.
1, concept transformation
According to the complexity, there are two ways to transform the theme concept: direct transformation and decomposition transformation. The direct transformation of concepts can be completed only by looking up the vocabulary directly, but the decomposition and transformation of concepts are much more complicated. In the process of concept transformation, indexer needs not only extensive knowledge, but also rich imagination.
2. Application of thesaurus.
In the process of writing academic papers, keywords can be determined according to "net" vocabulary. Especially medical academic papers should be paid more attention to.
Third, theme analysis is to choose keywords.
1, article comments.
Read the topic, make clear the subject object of the article, understand the author's intention and the content and focus of the article, and determine its main content and center, reference value and scope of application.
2. Theme refinement.
The refinement of the theme should be judged on the basis of careful reading of the manuscript, and the key sentences in the text should be highly accurate and concise, so as to grasp the main content of the essence and discard the secondary content.