• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.143-153
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• 2019

In this study, numerical simulations for the prediction of added resistance for KVLCC2 with varying wave steepness are performed using a Computational Fluid Dynamics (CFD) method and a 3-D linear potential method, and then the non-linearities of added resistance and ship motions are investigated in regular short and long waves. Firstly, grid convergence tests in short and long waves are carried out to establish an optimal mesh system for CFD simulations. Secondly, numerical simulations are performed to predict ship added resistance and vertical motion responses in short and long waves and the results are verified using the available experimental data. Finally, the non-linearities of added resistance and ship motions with unsteady wave patterns in the time domain are investigated with the increase in wave steepness in both short and long waves. The present systematic study demonstrates that the numerical results have a reasonable agreement with the experimental data and emphasizes the non-linearity in the prediction of the added resistance and the ship motions with the increasing wave steepness in short and long waves.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.60-60
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• 2018

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.255-255
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• 2017

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.504-511
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• 2015

In this paper, the results of evaluating the passenger comfort due to the standard deviation of acceleration in vertical and lateral direction regarding the ship response in irregular wave by ordinary strip method in regular wave and energy spectrum using linear superposition theory in order to evaluate the motion of experimental ship are as follows. According to the results of ship response, it was possible to find that, in order to reduce the motion of ship, a ship operating in bow sea was more stable than in quartering sea. In the results of analyzing the standard deviation of acceleration in vertical direction according to each component wave pattern, when there was a wave length of 56m and an average wave period of 6 sec, most of cases showed the peak value. And among them, the standard deviation was 0.35 which was the highest in head sea. And in case of lateral direction, the maximum value was shown in a wave length of 100m and an average wave period of 8 sec. And it was 0.16 in beam sea and ${\chi}=150^{\circ}$. In the evaluation of passenger comfort due to standard acceleration in vertical and lateral direction, it was 80% in head and bow sea. On the other hand, it was shown to be 15% in follow sea. Accordingly, when the expected wave height in a sea area where a training ship was intended to operate was known, it was possible to predict the routing of ship. And altering her course could reduce the passenger comfort by approximately 50%.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.193-198
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• 1996

In this study the RETRAN-03 code was modified to analyze the thermal-hydraulic transients under three-dimensional ship motions for the application to the future marine reactors. First Japanese nuclear ship MUTSU reactor have been analyzed under various ship motions to verify this code. As results, typical thermal-hydraulic characteristics of marine reactors such as flow rate oscillations and S/G water level oscillations are successfully simulated at various conditions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.1
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• pp.62-70
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• 2007

Marine casualties of vessel are serious problems on social and national aspects, because it results in sacrifice of lives, a great lose of properties and marine pollution. According to recent statistics of marine casualties of vessel, fishing boats are more likely to be ended in the casualty, and especially, small fishing boats cause much more accidents than any other big vessels. Most of marine casualties were caused by the human factors such as poor watch keeping, inadequate manoeuvering and negligent action for engine, etc. This study is intended to provide navigator of small fishing boat with a specific information of necessary to assist both the manoeuvering and the avoidance of capsizing. The manoeuvering characteristics of ship can be adequately judged by the results of typical ship trials manoeuvres. For this purpose, the author measured the roll responses of a small fishing boat in waves using the real sea experimental measuring system, and analyzed the experimental data by the statistical and spectral analyzing methods to get the characteristics of the roll motion responses of the small boat through the wave directions and the ship's speed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.3
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• pp.287-293
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• 2017

The purpose of this study is to keep the safety of the car ferry passengers and vessels by investigating and analyzing vessel safety management systems in Korea and China. To this end, we investigated Korea-China car ferries and the current status and causes of global marine accidents corresponding to the sizes of the vessels from Korea and China. Furthermore, we investigated car ferries' crew management and safety management. As a result of the analysis of the ferry accident, the causes of human error and ship's age were the greatest, but the ship's companies showed a negative stance regarding the age restriction. It seems that it is necessary to utilize the near-miss accident reporting system and differentiate the management of ship's aging. Also, it was analyzed that both the ship company and the crew of the ship need to strengthen their awareness of safety management.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.57-67
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• 2008

Recently, Korean shipbuilding industry is keeping up the position of world wide No. 1 in world shipbuilding market share. It is caused by endless efforts to develope new technologies and methods and fast development of IT technologies in Korea, to raise up its productivities and efficiency in shipbuilding industry with many kinds of optimizing methods including genetic algorithm or artificial life algorithm... etc. In this paper, we have suggested the artificial life algorithm with relay search micro genetic algorithm. and we have improved a defect of simple genetic algorithm for its slow convergence speed and added a variety of solution candidates with applying relay search simple genetic algorithm. Finally, we have developed intelligent agent system for ship CAE modeling. We have tried to offer some conveniences a ship engineer for repeated ship CAE modeling by changing ship design repeatedly and to increase its accuracy of a ship model with it.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.3
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• pp.599-615
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• 2013

This paper aims to empirically explore how the partnership between the two industries influences on the satisfaction of ship management companies. In addition, this paper intends to provide relevant information to enhance the competitiveness of ship repair companies by revealing the causalities of variations consisting of the partnership between ship management companies and ship repair companies. It revealed what characteristics are embedded in the partnership between ship management companies, and how the consisting factors of this partnership influences on satisfaction throughout prior factors. And this paper explored the variables that influence on the satisfaction of ship repair companies.

• Journal of Fisheries and Marine Sciences Education
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• v.24 no.6
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• pp.862-871
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• 2012

The purpose of this paper is to find out the applicability of relationship marketing concept in a professional ship management context primarily on ship management service business. The dramatic growth in ship management industry leads to the intensified competition among professional ship management companies in the world. Thus they have tried to find out ways of ensuring competitiveness to be a market leader in this industry. The fundamental base of marketing is that it involves exchanges. Professional ship management involves a series of transactions and exchanges between client and ship manager. Ship management companies will ensure competitiveness by applying the concept of relationship marketing to real practices.