nonstationary filter的用法和樣例：
例句
- A reassignment method for nonstationary time-frequency joint analysis is introduced.
介紹了非平穩信號時頻聯合分析中的重排方法。 - Based on the features of existing structure, the nonstationary random process model of resistance for existing structure is proposed.
根據服役結構的特點，提出了服役結構抗力的非平穩隨機過程模型。
