由于半周期脉冲而与光谱迪拉克的偏差
Audun Theodorsen1, Gregor Decristoforo1, Odd Erik Garcia1
1UiT The Arctic University of Norway, Department of Physics and Technology, N-9037 Tromsø, Norway.
Physical review. E
|November 18, 2025
概括
这项研究模拟了弱非线性系统中的半周期性波动. 与严格周期性的偏差,如动或更新过程,有效地将迪拉克从频率功率光谱密度中移除,揭示脉冲光谱.
科学领域:
- 非线性动力学是一种非线性动力学.
- 随机过程是指随机的过程.
- 信号处理 信号处理
背景情况:
- 频率功率光谱密度的周期性振荡表现为迪拉克子.
- 弱非线性系统或接近不稳定值的系统表现出扰乱周期性.
- 偏离严格的周期率会导致复杂的光谱特征.
研究的目的:
- 审查和讨论半周期波动的随机模型.
- 呈现新的结果,扩大模型的适用性.
- 分析周期性偏差对光谱性质的影响.
主要方法:
- 描述波动作为固定形状脉冲的叠加.
- 导出频率功率光谱密度的闭式表达式.
- 分析随机脉冲幅度和脉冲到达时间 (和更新) 的偏差.
主要成果:
- 一般光谱是一个由脉冲光谱调节的迪拉克子.
- 和更新过程有效地去除了迪拉克,留下脉冲光谱.
- 喷射调节更高的波,而更新则导致光谱扩大.
结论:
- 随机模型有效地描述了半周期性波动.
- 与周期性的偏差显著改变频率功率光谱密度.
- 该模型适用于热对流中的动能波动等现象.
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