这个和学术关系不大,不过我也看到有文献中求。例如
Rathje, E.M., Faraj, F., Russell, S., and Bray, J.D. 2004. "Empirical Relationships for Frequency Content Parameters of Earthquake Ground Motions," Earthquake Spectra, Earthquake Engineering Research Institute, 20(1), pp. 119-144