According to the characters of the ciphertext database, the major factors to create a ciphertext index are analyzed.

Aiming at the data secrecy problem in database, we have analyzed some present encryption mechanism and put forward a new query method based on ciphertext index.

A cryptograph index technology based on query probability in DAS model;

Database Cryptograph Index and Secret Key Management Technology;

Although achievements have been made,there still are problems of long responding,expensive cost and low security of cryptograph index after encrypted that are not solved yet.

We must promote teachers capabilities in searching literature and librarians integrating competence, and we must initiate the course of literature searches in order that libraries and internet can be accessed with rapidity and efficiency.

In most of the teaching materials and the reference books of the type of Chinese ref- erence books, the designed exercises of the literature searches are fragmentary to some extent, and they are not very practical.

Application of TotalCopy in hospital library literature retrieval;

Evidence-based medicine literature retrieval in MEDLINE database;

The experience of continuing education of literature retrieval in the library of universites of traditional chinese medicine;

Research of Enterprise Text Retrieval Model Based on Ontology;

A Pilot Study of Latent Semantic Indexing for Text Retrieval;

A Restricted Domain Text Retrieval System;