The correlation coefficient stationary process in which the mean and variance vary with time is familiar in engineering,and the traditional correlation function stationary process is just a special case of that.

Second,it presents a forecasting model on the relative investment effect level of the next period investment using stationary process theory,thereby an optimal model on investment combination .

Moreover we investigate the relations for Markov processes, martingales and stationary processes systematically.

The paper explains an important distinction between unit root processes and stationary processes.

Some topics, such as the implication of non-stati on ary, equivalence of non-stationary random process, and power law process, are st udied.

By analyzing the non-stationary random process evolutionary spectra given by Priestly,the bi-modulation function and bi-modulation model of non-stationary earthquake ground motion were proposed.

Through the effects of the electromechanic characteristic parameter s change on the mechanic rotor have been considered,the electromechanic coupling system is composed of converter based on SPWM,cage type asynchronous machine and mechanic rotor has been established to study the rotor s nonstationary process.