• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.172-177
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• 1995

The maneuverabilities of the M.S. TAMYANG are studied, based on maneuvering indices and the data obtained from her Z test. The results obtained are summarized as follows : 1. The maneuvering indices K'and T'of the M.S. TAMYANG are 0.9464, 0.6895 at 10$^{\circ}$Z test and 0.8651, 0.4224 at 20$^{\circ}$Z test and 0.8349, 0.4328 at 30$^{\circ}$Z test respectively. The above calculated values K', T'showed that her maneuverabilities are more effective when the rudder is used to small angle than to large angle. 2. As her maneuvering indices K'and T'at 10$^{\circ}$Z test are smaller than the standard maneuvering indices of fishing boats, her turning ability was found to be lower but her obeying ability higher. 3. The running distance of a turn at her 10$^{\circ}$Z test was about 8.8 times her own length and she was considered to have good maneuverabilities synthetically.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.1082-1087
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• 2021

The propeller shaft has different pattern of behaviors at each static, dynamic, and transient condition to a ship shaft system due to the effects of propeller weight and eccentric thrust, which increases the potential risk of bearing failure by causing local load variations. To prevent this, the various research of the shafting system has been conducted with the emphasis on optimizing the relative slope and oil film retention between propeller shaft and stern tube bearing at quasi-static condition, mainly with respect to the Rules for the Classification of Steel Ships. However, to guarantee a stability of the shafting system, it is necessary to consider the dynamic condition including the transient state due to the sudden change in the stern wakefield during rudder turn. In this context, this study cross-validated the ef ect of propeller shaft behavior on the stern tube bearing during port turn operation, which is a typical transient condition, by using the strain gauge method and displacement sensor for 50,000 DWT medium class tanker. And it was confirmed that the propeller eccentric thrust change showing relief the load of the stern tube bearing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.497-503
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• 2018

Passenger ships and training ships have a common feature in that they serve many passengers. Thus, safe navigation is very important. During normal sailing, a ship may turn using various types of steering, including maneuvers to avoid collisions with dangerous target. When a ship turns, a heeling angle occurs. If trouble arises during sailing, a dangerous heeling angle may result or a capsizing accident. In this study, the heeling angle during turning was measured through experimentation with two training ships similar to passenger ships. These findings were compared with theoretical formulas for heeling angle when turning. We confirmed that the limit of the maximum heeling angle estimation using heeling angle formula when turning presented in IMO stability criteria. In addition, it was confirmed that the maximum estimated heeling angle can be reached by applying the result calculated in the theoretical formula 1.4 times when turning right and 1.1 times when turning left to reflect sailing speed when of rudder hard over. It is expected that this study will provide basis data for establishing safe operation standards for the prevention of dangerous heeling angles when turning.