Abstract: The validity of real time data and CPU processing capability is a contradiction in the cyber physical system (CPS).While increasing the sampling frequency can guarantee the validity of the real time data,it can also increase the CPU workloads and reduce the system’s computing power.Firstly,this paper used the semantic features of real time data to establish the validity model of the data.Then,by setting the pre-scheduling task during the idle period of the CPU,making good using of the data validity model,setting the new validity interval and the start time of the update transaction of the real time data,the CPU execution time was reduced.Finally,the strategy based on semantic model was evaluated systematically on the parameters such as rotation,revolution and oil pressure of cotton picking ingot.The CPU load can be reduced by about 15%.

Key words: Real time data,Semantics model,Validity protection,Cyber physical system