• Journal of Navigation and Port Research
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• v.26 no.1
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• pp.1-7
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• 2002

A coastwise chemical tanker sailing at full speed has capsized in calm water and while turing. We investigate reasons of the accident and demonstrate that a proper correction for the free surface effect of the liquid cargo has not been practiced in the initial design stage and that the bow-sinkage induced in sailing has weakened the form stability of the ship. It is also shown that the liquid cargo shift occurring in turning generated a significant outward heel moment.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.465-471
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• 2003

A coastwise chemical tanker sailing at full speed has capsized during turning in calm water. In the previous paper, we investigated the reasons of the accident by demonstrating the proper correction for the free surface effect of the liquid cargo and the bow-sinkage effect. In this paper, we also carry out model experiments of a transverse pressure under the seawater and an outward heel moment according to the heel angle and rudder angle, on the basis of radius of turning circle, ship's speed and drift angle of model ship occurring in turning. It is also shown that the flooding of seawater onto the deck occurring in turning generated a significant outward heel moment and increased the vertical distance between the center of gravity of the ship and the center of lateral water drag.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.269-269
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• 2019

The ships are turning for the purpose of collision avoidence and change of course. It is possible that ships have capsizing accident when improper loading of cargo and excessive use rudder angle in turning. It is difficult for navigation officers to recognize the danger of heeling during a turn, because the dynamic state of the ship changes in real time. Thus, in this study, ship's heeling angle was predicted during turning using the maneuverability indices estimated from the ship's autopilot. The maneuverability indices estimated through the Kalman filter of Autopilot is real-time predictable. The turning radius was obtained from the estimated Index of turining ability and calculations of the heeling angle were possible in turning. It is intended to be used as a basic data on the prevention of danger heeling angle during turning.

• Journal of Navigation and Port Research
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• v.40 no.6
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• pp.353-360
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• 2016

The International Maritime Organization (IMO) has issued international standards for ship maneuverability and stability. These have been established to improve marine safety and influence the direction of research. The previous literature has been researched, but there are few studies on the relationship between ship maneuverability and stability. This study carried out a fundamental experiment to quantitatively evaluate that relationship. Radius of turn and maximum heel angle depending on changing were analyzed through a turning test using a free running model ship. The test results show the change tendency of decreasing turn radius and increasng maximum heel angle according to a GM decrease. A rough estimate equation is proposed to predict the change tendency on radius of turn and angle of maximum heel as GM decreases. Many ships can suddenly experience reduced GM due to unexpected reasons during sailing. The results in this study can be used as fundamental data to estimate a ship's tactical turn diameter and variable heel angle for steering as GM decreases.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.42-43
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• 2017

선내시스템 원격모니터링 서비스는 원격지 해역을 항행하고 있는 선박의 주요정보(화재, 경사, 탱크레벨, 기관 및 항해장비 등) 데이터를 이용하여 항행/화재/내항성 등의 선박의 이상상태를 감지하고, 이를 선박 운항자에게 서비스하는 시비스로서 선박 사용자와 육상의 이네비 센터 운용자가 효율적으로 이용할 수 있는 사용자 UI를 개발하고 있다.

• Journal of Korea Fishing Vessel Association
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• v.3
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• pp.46-50
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• 1980

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.6
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• pp.654-659
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• 2016

Recently, the passenger ship 'Sewol' capsized with an abrupt inclination while she was making a small angle alteration. It is very important to fully understand the concepts, causes and relevant corrections for a ship's transverse inclination, which is classified into heel, list and loll. In this study, the concept, development and calculation of loll were well considered and the actual magnitude of the angle of loll was simulated in a box-shaped model-ship experiment. The experimental values and its development according to different values of negative stability were compared with calculated values. In the results, experimental values for the angle of loll coincided closely with calculated values and the model inclined symmetrically on both port and starboard sides indicating an outstanding feature of loll. This study is expected to expand the concept of loll and help in the analysis of capsize incidents with unknown causes. Further experimental research or case studies concerning the risk of inappropriate correction for loll arising from misunderstandings will be needed.

• 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.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.2
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• pp.250-257
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• 2012

Currently, large vessels and structures are manufactured into set of blocks, then assembled on-site. Large scale ships that weigh thousands of tons are built in a short period by making set of large blocks and assembled on a dock or a land. When a transporter encounters a slope during the process of transporting blocks, the heavy goods loaded on the transporter can be tilted. Further, if the vehicle moves down the slope in this state then it can cause an accident of overturn of loaded goods. The research has been taken into account to calculate the center of gravity of the transporter carrying heavy objects on a leveled surface or the three dimensions. In addition, ZMP (Zero Moment Point) is used to calculate the allowable slope degree that objects are predicted to overturn. Through the simulation, the objects' stability is tested when it is climbing the slope.

• Journal of Navigation and Port Research
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• v.43 no.4
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• pp.231-236
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• 2019

As ships become bigger, faster, and diverse, transportation has increased the usage of marine vehicles. However, ship accidents are increasing. Ship accidents cause loss of life and property as well as environmental disasters. The occurrence of ship accidents causes enormous economic and environmental impacts. Notably, in the case of passenger ships, methods for preventing ship accidents are being discussed to avoid losing numerous human lives. The purpose of this study is to provide essential data for evacuation before reaching the dangerous time by predicting the time to reach the risk of capsizing based on the heeling angle of the passenger ship. Based on sinking accidents between 2012 and 2016, we set up specific scenarios and simulated the PRR1 data using commercial software MOSES V20. In the case of the linear equation, the simulation results showed a low error rate because the simulation data showed the linear graph. In the case of the quadratic equation, the error rate was low at the beginning but showed a high error rate at the subsequent angle.