second-order stationary process

例句：

1. 1. The model is designed to simulate the behavior of a second-order stationary process.
   该模型旨在模拟二阶平稳过程的行为。
2. 2. In economics, a second-order stationary process is a type of time series that exhibits no trend or seasonality.
   在经济学中，二阶平稳过程是一种没有趋势或季节性的时间序列类型。
3. 3. The data collected from the experiment showed that the system was in asecond-order stationary process.
   从实验中收集的数据表明，该系统处于二阶平稳过程。