• Journal of the Society of Naval Architects of Korea
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• v.58 no.2
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• pp.97-104
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• 2021

Together with the emerging of the Eco-ship, the application of large-diameter and high-efficiency propeller required more careful attention than before in the design of the shafting system. After the adoption of Environmentally Acceptable Lubricants (EAL) to the stern tube lubrication oil, a number of aft stern tube bearing accidents have been reported, and a variety of institutions have actively conducted research on the cause relationship. This study attempted to find the cause of the accident by measuring the alignment of the shafting system of a medium-sized product/chemical tanker with aft stern tube bearing damage and analyzing the reaction force of each bearing. In addition, a reasonable solution to the correction of the shaft alignment was suggested and the feasibility was reviewed. Through various measured data and analysis, the actual installation of shafting system was slightly different from the design drawing condition, but it was found that each bearing load distribution was within the allowable range. Therefore, it was confirmed that the cause of this accident was due to the dissatisfaction the misalignment slope of aft stern tube bearing rather than the effect of the bearing overload. As a solution to this cause, countermeasures such as double slope were suggested in the aft stern tube bearing, and the characteristics of EAL also seem to have an indirect effect.

• Journal of Ocean Engineering and Technology
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• v.32 no.6
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• pp.433-439
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• 2018

An investigation was conducted to determine whether the changes in the maneuvering forces and moments acting on a hull could be affected by changing the vertical center of gravity (VCG) of a tanker. The changes in the hydrodynamic forces and moment acting on a hull according to the restraint conditions of motion were examined using CFD for cases where the VCG was located at the design draught (100% of draught), under the design draught (75% of draught), and at half of the design draught (50% of draught). The following motion restraint conditions were selected: (1) fixed restraints for everything; (2) heave, pitch, and roll free restraint; and (3) heave and pitch free restraints. It was found that restraint condition (2) had the best agreement with the model experiment results. In addition, it was found that the hydrodynamic forces and moment acting on the hull with restraint condition (2) could be greatly affected in the model tests and CFD calculations by the various configurations for the vertical center of gravity of the hull. Finally, it was concluded that the location of the vertical center of gravity of the hull could be an important factor when more accurate hydrodynamic maneuvering forces and moment are estimated.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.3
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• pp.175-181
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• 2021

This study describes the model tests in ice according to the frictional coefficient of an ice-breaking ship and the change in ice resistance by the analysis method for each component of ice resistances. The target vessel is a 90K DWT ice-breaking tanker capable of operating in ARC7 ice conditions in the Arctic Ocean, and twin POD propellers are fitted. The hull was specially painted with four different frictional coefficients on the same ship model. The total ice resistance can be separated by ice breaking, ice buoyancy, ice clearing resistances through the tests in level ice, pre-sawn ice and creep test in pre-sawn ice under sea ice thickness of 1.2 m and 1.7 m. Ice resistance was analyzed by correcting the thickness and bending strength of model ice by the ITTC correction method. As the frictional coefficient between the hull and ice increases, ice buoyancy and clearing resistances increase significantly. When the surface of the hull is rough, it is considered that the broken ice pieces do not slip easily to the side, resulting in an increase in ice buoyancy resistance. Also, the frictional coefficient was found to have a great influence on the ice clearing resistance as the ice thickness became thicker.

• Proceedings of the Safety Management and Science Conference
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• 2012.11a
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• pp.215-223
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• 2012

Or maybe moving dangerous goods tanks of motorists excluded from the scope of the supervision of the fire department and fire prevention education as a blind spot on the part of a large party evidence of markers of contamination loading of dangerous goods according to the type of education that can be handled only by preparing the institutional arrangements accident is blocking the moving path of Dangerous Goods moving tanks and loading dangerous goods on fire budget move the path that corresponds to the report received by securing the extinguishing agent is required to neutralize the ash and fire suppression and repression through skills training from large disasters in advance blocking devices should prepare that will.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.2
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• pp.233-243
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• 2009

The strengthened regulations for atmospheric emissions from ships like MARPOL Annex VI have caused a necessity of new, alternative power system in ships for the low pollutant emissions and the high energy efficiency. This paper attempts to investigate the configuration of SOFC system for LNG tanker taking into account the safety and to analyze the influence of design parameters on the system performance. The simulation results provide the basic data for the design and efficiency improvement of SOFC system and indicate the guidelines for the safe system operation.

• Journal of the KSME
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• v.31 no.3
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• pp.267-275
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• 1991

LBB 설계법은 오늘날 같이 플랜트의 대형화 및 복잡화함에 따라서, 균열이 발생하였다고 하여도 기기의 점검시 발견하지 못하는 수가 있을 것이다. 이러한 경우에 있어서 LBB 설계법은 fail safe design으로서 만일의 손상이 발생하더라도 플랜트의 안전성 및 경제성 확보를 위하여 매우 중요한 설계법이다. 이 LBB 설계법은 위에서도 설명하였듯이 선진제국에서는 상당히 연구가 진전되어 있으나, 우리나라에서는 이 분야에 연구가 전혀 없는 실정이다. 특히 에너지자원이 부족한 우리나라로서는 LNG, LPG 가스의 수입에 있어서, 이러한 저온가스를 운반할 tanker의 개발에 있어서도 LBB의 확보가 중요한 것이다. 또한 발전에너지원을 석유에만 의존하는 현재의 추세에서, 우라늄 등에 의한 원자력발전으로 대체되어 가고 있는 현재 전 발전능력의 약 50%를 의존하고 있는 실정이다. 이러한 면에서 실제의 구조물이 일시에 파단이 일어나지 않고, 파단 신뢰성이 충분히 높다는 것을 실증하여 둔다는 것은 안전성평가상 지극히 중요한 것이다.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.3
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• pp.455-460
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• 2008

The flammable gas monitoring system is to be provided in cargo pump rooms of tankers in accordance with the requirements of SOLAS regulations, and flammable gas detectors are to be arranged in a proper position. In this paper, simulation tests and CFD analysis are carried out under the actual ventilation conditions of pump rooms in the ship in service. Based on the results, a new guidelines for an arrangement of flammable gas detectors are suggested.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.227-231
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• 2001

In this paper recently catastrophic oil spills from tanker casualties have polluted the marine environment. The Sea Prince casualties are analyzed and the systems to be introduced are considered. Also, the establishment of the national contingency plan and the decision-making procedure based on technical analysis are described. Based on the discussions the Rapid Response Technical Support System is derived for the support of salvage and oil spill removal operation. The System will contribute to the protection of life and assets from the marine casualties and to keeping the clean and safe ocean.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.610-613
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• 2000

Recently catastrophic oil spills from tanker casualties have polluted the marine environment. In this paper, the Sea Prince casualties are analyzed and the systems to be introduced are considered. Also, the establishment of the national contingency plan and the decision-making procedure based on technical analysis are described. Based on the discussions the Rapid Response Technical Support System is derived for the support of salvage and oil spill removal operation, The System will contribute to the protection of life and assets from the marine casualties and to keeping the clean and safe ocean.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.51-54
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• 2006

최근 국내 중형급 조선소에서는 케미컬 탱커선을 주력선종으로 건조하고 있다. 하지만 선형개발 기술이 미비하여 저항감소 선형개발에 소홀하였다. 또한 기존 대형선박의 선형을 그대로 사용하기 때문에 추진효율이 떨어지고 많은 선수저항이 발생하여 선속에 큰 영향을 미치게 된다. 이에 본 연구에서는 CFD이론 해석을 통해 선형특성을 파악하고 저항감소 및 추진 효율 향상을 위해 실적선과 개발대상선의 모형시험을 통하여 선수저항 성능을 비교, 분석하여 저항감소 선수선형을 개발하였다.