large ship motions which come to the interruptions of cargo handlings are generated by considering the long period wave.
Fig.-7 The calculated ship motions at interruption for 15,000DWP at 6:00, Sept 1 with the long period wave
Considering the long period waves, we try to evaluate the operation efficiency of cargo handlings during the three months again. The results are summarized in Table..6. Aswell as the investigations of the ship motions at the interruptions, the operation efficiency is evaluated well by the inside wave including the long period waves.
Table-6 Comparisons of operation efficiency
5. CONCLUSIONS
We investigated the influences of long period waves on the evaluation method for operation efficiency of cargo handlings. The obtained results are summarized as follows.
1) In accordance with general weather conditions and characteristics of the harbor, it is necessary to consider the long period waves for reproducing the ship motions at interruptions of cargo handling.
2) It is necessary for an evaluation method on the operation efficiency from the view of moored ship motions to consider influences of the long period waves.
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