Free Access

Fig. 4

thumbnail

For comparison, the top panel shows the semi-amplitude spectrum before prewhitening, the subsequent panels represent the semi-amplitude spectrum after prewhitening 20, 40, and 60 frequencies, respectively. The red lines exhibit the critical level at the significance level of 0.01 under a null hypothesis of white noise.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.