spectral decomposition of stationary process

例句：

1. 1. Spectral analysis is a technique used to identify the properties of materials based on their absorption and emission spectra.
   光谱分析是一种技术，用于根据材料的吸收和发射光谱来识别其特性。
2. 2. The researcher used a spectrometer to measure the spectrum of the light emitted by the device.
   研究者使用分光计测量了设备发射的光的光谱。
3. 3. In the study, scientists analyzed the spectral data to determine the chemical composition of the sample.
   在这项研究中，科学家们分析了光谱数据，以确定样本的化学成分。