2. Periodical papers
Three-dimensional catalogue
4, C summary
5. Scientific journals
6, D standard literature
7.d paper
8. newspapers
9. Same theme
10, A 5, 22 categories.
1 1, an s class.
12, c reference backtracking method
13, database
14, b storage and retrieval
15, patent announcement
16, a national standard
17, Wanfang database resource system
18, name of C periodical, annual volume, page numbers of published papers.
19, headline
20, C a and b and c
Different fields have different definitions of information. The definition of information in library and information science is that information is the external expression of objective attributes and motion state.
Knowledge is people's understanding of the existence and movement law of objective things.
Literature is the material carrier of all recorded knowledge.
The relationship among information, knowledge and literature can be summarized as follows: information is the raw material for producing knowledge, knowledge is the systematic information of human beings, and literature is the carrier for storing and transmitting knowledge and information.
Information is not equal to knowledge, and knowledge is an important part of information. This inclusive relationship between information and knowledge can be expressed as: information is greater than knowledge. Among all things in nature, information is a form that the material world represents its existence.
Information, tangible, independent of action and decision-making, changes in form after processing, material products, unrelated to the environment, renewable; Knowledge, intangible, is related to action and decision-making. After processing, it changes thinking, spiritual products and environment, and changes meaning. It can only be transferred after learning and cannot be copied.
Knowledge is a large amount of organized information, and obtaining knowledge depends on obtaining information; Information is the intermediary of knowledge formation and dissemination, not knowledge itself. Knowledge is useful information after careful study and understanding, and it is the product of human processing information. Not all information can become knowledge. In the information age, a large amount of information from many complex objects can only be truly transformed into knowledge by means of modern information means and by mastering the cognitive subject of modern information science and technology.
In database retrieval, when the number of documents detected is small, it may be caused by the following reasons:
① The search term is misspelled;
(2) Omission of important synonyms or implied concepts;
③ Search words are too obscure and specific;
④ No truncation operator is used;
⑤ Too many position operators and field operators are used;
6. Logic is too strong and too strict.
⑦ The number of retrieved databases is small.
Therefore, it is necessary to expand the search scope and increase the detection amount of literature information. Specific measures are as follows:
① Reduce the AND operator and add related search terms with 0R; Add 0r to all subordinate words; Add a superior predicate; Adopt superior grade; Eliminate common concepts in the database.
(2) Use the word segmentation system (? ) After words with the same stem. );
③ Delete existing field restrictions and positional operator restrictions (or use less restrictive positional operators).
(4) Correcting wrong search terms;
⑤ Add enough interrogative words,
⑥ Use narrative words as intimate keywords;
⑦ Select index words with high login number;
Finally, we gave up single-database retrieval and chose cross-database retrieval.
Supplement to the question:
1. Literature can be divided into first-class literature, second-class literature, third-class literature and zero-class literature according to its processing depth.
2. The connotation of information literacy includes information consciousness quality, information ability quality and information moral quality.
3. The main types of serial publications are periodicals, newspapers and yearbooks.
4. The three elements of literature are information content, recording symbols and carrier materials.
Chinese full name of 5.5. CNKI is a national knowledge infrastructure.
6. The common methods of information retrieval are: common method, retrospective method and comprehensive method.
7. Patent has three meanings: patent document, patent right and patent invention.
8. The main body of standard documents is technical standards.
9. The literature sources of periodical papers include the periodical names and annual volumes of published papers.
And start and end page numbers.
10. The three major agricultural literature databases in the world refer to CABI, AGRIS and AGRICOLA.
1 1. In computer information retrieval, Boolean logic operators used to match search terms and limit search scope include: and(*), or(+) and not(-).
12. The information index of the detection degree of the required information is the recall rate.