This paper expounds the importance of the composition of the of abstract thesis,points out the problems existing in the composition of the abstract of thesis,illustrates four key elements of the composition of the abstract of thesis,and introduces some methods for composing the foreign abstract.

The construction and application of CPPI abstract Chinese-English parallel corpus;

Study on accuracy of data in Abstracts of published research articles;

Relevance patterns of messages: between the first sentences ofabstracts and the titles of the corresponding engineering journapapers;

Analysis on common problems in writing Chinese abstract of Agricultural Sci-tech Papers;

This paper analyses some subnormal phenomenon of Chinese abstract of technology peridoical and points out the problem that should be noticed in writing chinese abstract.

Writing guide of English abstract;

Common mistakes and nonstandard expressions in English abstracts of medical literatures;

Writing guide of title in English abstract;

A Constructing Algorithm of Message Digests Based on Graphs Isomorphism and One-Way Permutation;

Aiming at the security of electronic commerce,the paper introduces the digital signature based on cryptography;The paper presents an application project of digital signature according to RSA algorithm and MD5 message digest algorithm.

The new metho d based on watermark, message digest and public key cryptography technology is p roposed to verify image integrity and senders authentication: any changes of p ixel values and changes in image size due to scaling or cropping as well as bloc k swapping in images or corr.