In this study it will be discussed how to solve the problem of discomfort from rolling motion on the fishing boats. Most discomfort is caused by the short cycle of rolling due to the light weight of the boats. The light weight is due to the FRP material which dries a boat. A way to improve the feeling of boarding by using fish hold was researched. The experiment was done on experimental fishing boat made by FRP in Jeju. An existing fish hold was designed and manufactured through the rolling test and that was used for a marine experiment. The rolling condition of the U-tank boat ideally designed was compared to that of an existing fishing boat using the same conditions. The experiments were carried out two times on the stop engine in the outward Sehwa fishing port, which the experimental data had analysed for effects of rolling reduction to compare the U - tank with the of exiting fish hold. The results were confirmed that the U-boat tank in the roll period and GoM were more safe than the existing fish hold and the average amplitude and significant of rolling angles were decreased relatively.

The objective of this study was to manufacture the sea water cooling apparatus for fish hold storage to extend the freshness of fish. Using the sea water cooling apparatus manufactured, it makes observations on the physicochemical and sensual properties of mackerel such as ATP and its related compounds, K-value, VBN, TMA, TBA, salt-concentration and skin color through storage. The results of this investigation showed that the values of physicochemical properties such as ATP and its related compounds, K-value, VBN, TMA, TBA increased gradually during storage in sea water cooling apparatus manufactured and the changes of skin color was inhibited also. From these results, it could be suggested that developed sea water cooling apparatus is effective in shelf-life extension of fishes.