The present paper, at first, presents the author's understanding of the problem caused by the use of ITTC (International Towing Tank Conference) 1957 Line in conjunction with three-dimensional analysis. Then, how the ideal friction line should be within the range of model Reynolds number is discussed. As a conclusion of this paper, the answer to the question "Should ITTC 1957 Line be revised?" is as follows. It is "Yes" in a sense that ITTC 1957 Line prepared for two-dimensional analysis should be revised, if we employ three-dimensional analysis. It is "No" in another sense that the expected gain by the revision of the friction line would be almost negligible and, on the other hand, we have to expect the setback caused by changing from the well-accustomed line to new one.

A high accuracy edge measurement method of edges of components using point cloud data by 3D laser scanner is proposed in this paper. The proposed method consists of two parts: method for shape measurement of edges by using points of side faces of the components and method for length measurement of edges by attaching the 3D targets. At the experiments with a surface plate and a curved shell plate, the results give suggestions for having possibility of applying this proposed method for actual shipbuilding components.

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There has been hot discussions on the characteristics of wave-induced pressure fluctuation on the side shell of VLCCs, since considerable number of fatigue cracks were found on side-longitudinals of second generation VLCCs. In Japan, it was mainly dealt with by SR-216 Panel, where a full-scale measurement on a typical second generation VLCC, tank experiments on a scaled model and theoretical investiga tions were carried out. The main themes of the discussion seem to be whether characteristics of pressure fluctuation is predictable even for small values of wave-length to ship-length ratio like 0.1-0.3 and how peak-to-trough value can be obtained of wave-induced pressure fluctuation on the side shell close to the load-water-line. Tank experiments on a scaled-model ship were carried out at Nagasaki Experimental Tank of Mitsubishi Heavy Industries to answer the questions, and it is shown that measured results agree with calculated results by strip method after a simple correction on non-linearity effect caused by the crossing of free-surface.Results of long-term prediction with the same correction also show good agreements with the results of the full-scale measurements.

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