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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Map of the maximum frequency at 30 min intervals during the 44 days of a complete production cycle. The horizontal axis shows the hours of the day and night, and the vertical axis shows the days of the cycle.