SummaryIn order to estimate ship speed in actual seas it is important to calculate added resistance in waves with accuracy. Added resistance in waves usually appends the effect of wave reflection to added resistance due to ship motion. The effect is understood as the correction of the diffraction force in short waves. The conventional formula for the added resistance due to wave reflection was derived for large blunt ships. For fine ships such as a container ship, the estimation of the added resistance in short waves has poor agreement with the experimental result.We propose a practical correction method for added resistance in waves. From the point of accuracy the correction involves a tank test in the estimation of added resistance due to wave reflection. The test is conducted with different ship speed in short waves of a single kind of wave length. The correction method and the comparison with the experiments are presented here. Thereafter the influence on decrease of ship speed in actual seas is evaluated for a large container ship.

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In order to estimate decrease of ship speed in actual seas, it is important to calculate added resistance in waves with accuracy. Especially added resistance in short waves is one of the predominant factors inducing the decrease of speed for a large ship in relation to wave spectrum. Various calculation methods have been proposed for the added resistance in short waves. However those methods are proposed for blunt and low-speed ships, for example, tanker, bulk carrier, etc. Those methods give poor agreement with experimental data for fine and high-speed ships. To improve the estimation method, firstly numerical investigation on the effect of draft and frequency was carried out. Thereafter experiments of wall-sided models with motion fixed were conducted. From these results a new formula is proposed, which gives good agreement with the experimental results.

Reduction of green house gas from international shipping shall be put forward. For the reduction, it is important to promote to introduce ships of high energy efficiency to the shipping market. In actual seas a ship decreases her speed not only the deterioration and fouling effect but also by natural forces such as winds and waves. By design technique, ship propulsive performance in actual seas is able to improve. Hence ship propulsive performance in actual seas has much scope to improve the energy efficiency.We present a calculation method of decrease of ship speed in actual seas. From the point of accuracy, the method involves correction for added resistance in short waves combined with a tank test. As examples three kind of ship; a container ship, a car carrier and a bulk carrier are examined and the components of external forces acting on the ship are discussed.

A new surgical approach to apical segment lung diseases, including carcinomas and inflammatory diseases A new surgical approach to lung cancer and inflammatory pulmonary diseases has been developed. This approach focuses on diseases located in the apical segments of the lung and showing invasion or severe adhesion to the apical thoracic waD or to vital organs near the thoracic dome (including superior sulcus tumors). The conventional posterolateral approach leaves the surgeon "blind" because it forces the surgeon to perform the operation looking up through a tube from the bottom. This limited view makes accurate assessment of the surrounding vital organs involved in these diseases almost impossible and also increases the risk of injury to adjacent vital organs. The incision in this new approach allows extensive retraction of the scapula to provide easier access to the posterior chest waD. Because the incision curves upward anteriorly, rather than downward as usual, it gives excellent exposure of the apical anterior thoracic region. In the few cases in which we have used this approach, we have found that the surgical field is in plain view and that the operation is consequently safer and easier. So far we have not encountered any complications, and we can recommend this approach with confidence. (J