• 대한조선학회논문집
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• 제43권3호
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• pp.331-339
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• 2006

The objective of this paper is to calculate the fatigue strength for upper deck hatch corner insert plate of large container carriers without wave load analysis and global finite element analysis at the initial design stage. Wave load analysis and global F.E. analysis for three container carriers have been performed by GL(Germanischer Lloyd) procedure to propose the equation for hatch corner stress range which is the important factor in fatigue strength calculation. Considering the restraining effect of bulkhead, three types of equation, that is, single tight bulkhead, double tight bulkhead and support bulkhead have been proposed. Using the proposed equations, a simplified fatigue analysis based on GL rules has been performed for two container carriers of which fatigue strength analysis was carried out by GL. From the comparison between fatigue strength result of using the proposed equations and that of GL, it has been found that proposed stress range equations are useful for scantling of upper deck hatch corner insert plates for over 8,000 TEU class container carriers.

• 대한조선학회 특별논문집
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• 대한조선학회 2009년도 특별논문집
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• pp.52-58
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• 2009

Openings for access to cargo holds are cut on horizontal stringers in every bulkhead of container carriers. But, they are positioned at the edge of stringer width to make minimum space for access and these openings are required to be stiffened by owners and classifications respectively. In this paper, the cargo hold bulkhead stringers with openings for 6,500 TUE container carriers were reviewed by FE analysis to be conducted with the results of hold analysis for 6,500 TUE container carriers classed to GL, DNV, LR and BV respectively, and purpose of this paper is to establish yard's standard of the reinforcement for these openings.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.553-556
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• 2011

The primary aim of the present study is to propose new design formulae that can be used to evaluate the structural performance of breakwaters installed on container carriers under green water impact loads. A series of numerical analyses for green water impact loads inducing breakwater collapse have been carried out. The well-known fluid-structure interaction analysis technique has been adopted realistically to consider the phenomenon of green water impact loads. The structural behavior of these breakwaters under green water impact loads has also been carried out simultaneously throughout the transient analysis. A verification study of the numerical results was performed using the actual collapse incidents of breakwaters on container carriers. It would be expected that the proposed design formulae, based on the obtained insights, could be used as practical guidelines for the design of breakwaters on container carriers.

• 유통과학연구
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• 제15권11호
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• pp.59-72
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• 2017

Purpose - This paper evaluated the efficiency performance of the three major maritime transport markets and examined the determinants of the performance. The firms' revenue fluctuates with the changes of the economic cycle; hence it is important for them to set up business strategies to improve efficiencies. A lack of efficiency measurements for shipping firms leads to a significant gap in determining their overall performance. Research design, data, and methodology - Each of DEA scores was adopted for the evaluation and panel regression was used to examine the impact of determinants on the performance. The analysis included 50 shipping firms from three maritime transport markets as follows; 15 firms of container liners, 18 firms of bulk carrier and 17 firms of tanker carriers, and its period was from 2010 to 2016. Results - In the CCR model, container liners were the highest, tanker carriers were the second, and bulk carriers were the lowest in operation efficiency and financial efficiency. By region, operation efficiency and financial efficiency was high in the order of America, Asia, and Europe. Conclusions - This study suggests business strategies for maritime transport companies based on the analytical results of determinants of operational and financial efficiency.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권2호
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• pp.83-95
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• 2012

In the present study, the structural response of breakwaters installed on container carriers against green water impact loads was numerically investigated on the basis of the fluid-structure interaction analysis. A series of numerical studies is carried out to induce breakwater collapse under such conditions, whereby a widely accepted fluid-structure interaction analysis technique is adopted to realistically consider the phenomenon of green water impact loads. In addition, the structural behaviour of these breakwaters under green water impact loads is investigated simultaneously throughout the transient analysis. A verification study of the numerical results is performed using data from actual collapse incidents of breakwaters on container carriers. On the basis of the results of a series of numerical analyses, the pressure distribution of green water was accurately predicted with respect to wave mass and velocity. It is expected that the proposed analytical methodology and predicted pressure distribution could be used as a practical guideline for the design of breakwaters on container carriers.

• 한국항만경제학회지
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• 제34권3호
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• pp.133-158
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• 2018

2017년 초 한진해운의 파산에 따라 세계 컨테이너 운송시장에서 차지하는 국적선의 비중 및 역할이 현저하게 줄어들었다. 이에 우리나라의 수출입 기업 뿐만아니라 항만들도 위기를 맞게 되었다. 더구나 미국 트럼프 대통령이 촉발한 관세 및 무역전쟁은 북미 향발 화물의 증가에 부정적인 영향을 초래하고 있다. 반대로 초대형 선사들인 머스크나 CMA CGM과 자국 내 컨테이너 선사간 인수 합병한 중국 및 일본 컨테이너 선사들은 국내 유일의 세계 10대 국적 컨테이너 선사이던 한진해운이 파산함에 따라 선복 공급 감소의 반사이익을 얻고 있다. 수출입화물의 무역거래에서 외국적선사의 권력이 더욱 커지고 있다. 이에 따라 부산 및 광양 등 국내 항만은 해외선사와의 협상력 약화가 초래 되어 선사 유치가 더욱 어려워질 수 있다. 본 연구는 이러한 상황에서 사회연결망의 위상학적 분석과 LSCI 및 CPCI의 경제학적 분석능력을 결합하여 2007년과 2017년의 전 세계 컨테이너 운송네트워크를 비교하였다. 연구결과 항만의 역할을 파악할 수 있으며, CPCI가 중심성지수 및 물동량자료와 높은 상관관계를 갖기 때문에 별도의 중심성 분석 없이도 필요한 중심성지수가 갖는 의미를 활용할 수 있다. 본 연구결과를 우리나라 선사들의 기항 전략과 우리항만의 제휴항만전략 및 발전전략에 활용할 수 있을 것이다.

• 무역상무연구
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• 제71권
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• pp.127-146
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• 2016

There are two aims of this research: one is to verify the role of bill of lading and the method of delivery for container goods and the other is to suggest alternative methods for the crisis of bill of lading; that is, goods are arrived in ports but bill of lading is not arrived. The results of the analyses are as follows. First, delivery of container goods should be performed to exchange with bill of lading. Carriers should deliver goods to consignees to exchange with one among the number of issued bill of lading. In addition, when goods are delivered to consignees by the bill of lading, the other bill of lading is invalid. Second, there are several methods of delivery which are not exchanged with bill of lading such as letter of guarantee, surrender bill of lading, sea waybill, non-negotiable straight bill of lading and consignment of bill of lading to a captain. Delivery of container goods should be performed by exchanging bill of lading. In addition, there are two delivery methods by letter of guarantee: one is illegal and the other is legal. If there is damage for a bonafide-fide holder of bill of lading, carriers should make compensation for the damage. These methods consist of the delivery of goods which is not exchanged with bill of lading and there are two advantages of the methods; one is that consignees enjoy saving bonded warehouse fee and quick disposal after arriving goods and the other is that carriers immediately use vessels after unloading containers. However, the methods are based on utmost good faith between a seller and a buyer.

• 대한조선학회논문집
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• 제51권5호
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• pp.429-434
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• 2014

The main objective of the present study is to elucidate a correlation between ship resistances from computational fluid dynamics (CFD) and brake horse powers (BHP) from towing tank in container carriers. The tests were conducted for a range of combinations of trim conditions and speeds. To achieve this goal, 295 cases of numerical simulation have been performed using Star-CCM+ which had been statistically verified to predict ship resistances (Lee & Lee, 2014). Based on the normal distribution of resistance errors in all cases of the 4 container carriers, the confidence interval of numerical error was estimated as [-2.33%,+2.42%] with 95% confidence. The correlation coefficients between the ship resistances of CFD and the brake horse powers of the experiments were higher than 0.93. As a result, the numerical calculation of ship resistances is able to be utilized in order to provide a quick guidance in selection of the optimum loading condition.

• 대한조선학회논문집
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• 제47권3호
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• pp.306-320
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• 2010

Modern ultra-large container carriers can be exposed to the unprecedented springing excitation from ocean waves due to their relatively low torsional rigidity. Large deck opening on the deck of container carriers tends to cause warping distortion of hull structure under wave-induced excitation, eventually leading to the higher chance of resonance vibration between its torsional response and incoming waves. To handle this problem, a higher-order B-spline Rankine panel method and Vlasov-beam FE model was directly coupled in the time domain, and the coupled equation was solved by using an implicit iterative method. In order to capture the complicated behavior of thin-walled open section girder, a sophisticated beam-based finite element model was developed, which takes into account warping distortion and shear-on-wall effect. Then, the developed beam model was directly coupled with the time-domain Rankine panel method for hydrodynamic problem by using the fixed-point iteration method. The developed computational scheme was validated through the comparison with the frequency-domain solution on the container carrier model in linear springing regime.

• Journal of Ship and Ocean Technology
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• 제9권1호
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• pp.1-10
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• 2005

The procedures of model test and performance prediction for the CRP-POD propulsion ships, are studied. At the CRP-POD system, which are highly applicable to ultra large container carriers, RPM ratio of two propellers is not fixed, unlike conventional CRP system, and hence the power of each propeller must be predicted respectively. In this paper, a CRP-POD system is designed for 10,000 TEU class ultra large container carriers, and the characteristics of the CRP-POD system are experimentally studied. Finally, based on this study, the procedure of powering performance evaluation for CRP-POD propulsion ships is suggested. However, further studies on quantitative correction of the present procedure are required.