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Answer: Power-spectral-density (PSD) analysis is not well-suited for human-induced vibrations because this type of excitation is periodic, and not harmonic. PSD analysis evaluates the probabilistic response of a structure subjected to a range of harmonic frequencies. Probabilities are assigned to the likelihood of each harmonic load pattern, then a root-mean-square (RMS) formulation computes the approximate response expected at each applied frequency, and for each response parameter. PSD analysis is most suitable for fatigue behavior and applications similar to response-spectrum analysis.
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