The first breakthrough—from oil seepage to the anticlinal theory; The second breakthrough—from the anticlinal theory to the trap theory; The third breakthrough—from the trap theory to the petroleum system.

In this paper, therefore, the author, on the strength of a documentary research methodology, analyses the women-related theories and viewpoints of the "May 4 Movement" period, thus finding out their basic concept, central content and theoretical background.

This paper attempts to summarize the different features of these two models and to analyze the different theoretical backgrounds.

It s included selecting textbooks,cultivating students interest and ability,enlightening them on the theory background and ideological method,and applying interaction and various other teaching techniques in class.

This paper mainly introduces the reform in the method of teaching the course of functions of complex variable and integral transform, complete with discussion on problems like selecting suitable textbooks, cultivating students interest and ability, enlightening them on the theory background and ideological method, and applying interaction and various other teaching techniques in class.

Because of the price bottle-neck,efficiency of the auctions is affected by the price bottle-neck very much,this paper presents a new secure efficient electronic auction using knapsack theory and secret sharing scheme.