On the basis of chaos map,a theory of block ciphers key space expand combined with the idea of "one-time pad" by shanon is constituted.

The simulation results indicate that the cryptosystem can enlarge the key space and resist the brute attack.

Compared with other generators,it has several merits such as the unpredictability of the sequence,bigger secret key space,smaller storage space,simpler algorithm and easier to implement in addition to its long period,.

The algorithm encrypts data by one-time one-key and multiple encryption, its key space is big enough and can defend effectively ciphertext-only attack of network s illicit users.

This paper explains and analyzes the space expanding and substance spreading of the Urban Ten- thousand-meter Basic Grid Management, by means of the research achievement and accumulated experiences of Chengdu Digital Urban Management System throughout the developing process.

The paper employed Suzhou Industrial Park,Wuxi New Area and New Changzhou Northern Area as cases to analyze the spatial expansion of de- velopment zones and the characteristics of urban restructuring caused by the ex- pansion,based on which the optimiza- tion of urban spatial structure was fur- ther discussed.

Chinese cities generally confront the conflicts of the rapidly spatial expansion and the limited land resources.

People can have a right view on the stage in urbanization process and can predict the developing trend by studying the state of city spatial expansion,time-space regulations and motive mechanism.

The tourism space expansion of the Three Gorges Region will develop a Big Three Gorges Region Economic Circle.