Brief introduction of classified retrieval language;
The basis of retrieval is classification and index. The greatest contribution of manual retrieval stage to information retrieval is the generation of retrieval language specifications. There are many classifications of retrieval languages.
Classification language is a retrieval language that takes numbers as basic characters and classification numbers as the identification of subject concepts, and classifies and systematically arranges various concepts according to the nature of disciplines. Classified language is a language based on discipline system. Important classification languages at home and abroad include international patent list, Dewey decimal classification, Chinese library book classification, China Academy of Sciences book classification and so on. Classification languages can be divided into systematic classification languages, combined classification languages and mixed classification languages.
Introduction in other languages:
1, the first set of retrieval languages:
Refers to the pre-fixed identification system that describes the concept of information subject before retrieval, such as system classification language, title language, etc.
2. Subject language:
Topic language is a retrieval language with words as concept markers, that is, nouns, noun phrases or sentences in natural language are used as subject words to express various concepts, and all concepts are arranged in the order of words, regardless of their relationship. Topic language includes title language, unit language, narrative language and keyword language.
3. Code language:
It is a coding system that people study and put forward in order to improve the semantic ability of retrieval language. This code system generally indexes and arranges only one aspect of things.
4. Reference language:
It is a natural language established by using the mutual reference relationship between documents. This language provides a method to retrieve all the cited papers from the cited papers, so as to find relevant documents along the development process of a scientific thought.