Study Of The Security Principle Of Unique Codes

In a high-consequence system, its unexpected mill function always cause to a catastrophic disaster. So it must insure the safety of such systems in normal environments and in a broad range of ill-defined abnormal environments. Unique Signal (abbr. UQS) serves as a critical component out of the safety devices, which may be used to improve the safety class of the high-consequence system. This paper mainly studies the safety principles of UQS.In this paper, the safety problems and safety design techniques of high-consequence system were summarized, and the concept of UQS and the safety principles that related to UQS were introduced. The mathematical characteristics of UQS were demonstrated. And some influences to the safety of UQS were also discussed. Based on the characteristics that a UQS should possess, we investigated its coding method, as well as the choosing method of multiple UQSs that can be used in a same system. By the multi-step coding method we have created UQS of length 24.The creating software of UQS was also developed. This included the creation of UQSs of given length, comprehensive analysis of the distribution of individual events, transition pairs, runs, duplicate separate strings, and the linear complexity of UQS.