• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.195-200
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• 2010

Basing on the recommendation and guideline of IALA, Korean VTS authority made an instruction about the training and qualification of VTS operators, and three model courses for training have been performed at a training institute which has one VTS simulator. However, the simulator has not been enough to make training fully satisfactory because of several signs of limitations including inaccurate method for calculating ship's movement and inconvenient location for training. In this paper, a new simulator was proposed to make up for the weak points replacing the current simulator. The proposed simulator adopts mathematical model for calculating exactly ship's movement which heightens the effect of training with simulator. And also it can be used through Internet so as to make long-distance training possible without visiting the training center. The effectiveness and the convenience of training with the proposed simulator are expected to be improved.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.791-798
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• 2016

In this study, numerical simulations on the effects of bilge keel on roll motion were conducted. The numerical simulations were performed on a 110 m class PSV using the commercial viscous flow analysis software Star-CCM+. Before conducting the study on the 110 m class PSV, an additional simulation of DTMB 5512 was performed and compared with the experimental results to validate the feasibility of the numerical simulation. In the simulation on PSV, a nondimensional damping coefficient was calculated using a free roll decay simulation, and the response amplitude operator (RAO) for the roll motion was calculated with a nondimensional damping coefficient at two conditions (with/without bilge keel).

• Journal of Korea Ship Safrty Technology Authority
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• s.22
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• pp.34-53
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• 2007

In the case of hull material. large sized merchant ships are made of steel, on the other hand FRP or wood are used for small sized fishing boats. At present in Korea approximately 88,500 fishing boats are in operation of which 70% are made of FRP In the meantime, stainless steel is frequently used as shaft materials of the small-size FRP fishing boat. Namely, the kinds of shaft materials are STS 304(18Cr-8Ni), STS 316(18Cr-12Ni-2.5Mo steel) and STS 630(17Cr-Ni-Nb steel)etc. Among these things, STS 304 which is the cheapest and having ordinary corrosion resistance is most widely used as 2nd class shaft material. But, using STS 304 for shaft system material of the small-size FRP fishing boat on seawater environments entails a severe corrosion which causes shaft system troubles. Particularly, the corrosions tend to be concentrated of the stern and bow side, propeller shaft surface of inside of stern tube and the boat having no stern cooling pipe line system. As a solution for those problems, research on the ways to mitigate corrosion on the part of 2nd class stainless steel shaft have been undertaken. In the result, not only clarification for the reason of corrosion of the part of stainless steel shaft used mainly for the small-size FRP fishing boat was done, but also most optimal corrosion protection system was developed by experimenting shaft's protection simulation based of the electrochemical cathodic protection principle. In addition, verification through the field test on the optimal cathodic corrosion protection method by means of aluminum sacrificial anode was carried out. In this study, effective and economical shaft's protection system is suggested to the small-size FRP fishing boat operator by substantiating the results obtained from the research on the optimal cathodic protection.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.125-134
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• 2023

In this paper, we propose an efficient surveillance RADAR(RAdio Detection And Ranging) interface control unit(ICU) design in the naval combat system. The proposed design applied a standardized architecture for modules that can be shared in ship combat system software. An error detection function for each link was implemented to increase the recognition speed of disconnection. Messages that used to be sent periodically for human-computer interaction(HCI) are now only transmitted when there is a change in the datagram. This can reduce the processing load of the console. The proposed design supplements the radar with the waterfall scope and time-limited splash recognition in relation to the hit check and zeroing of the shot when the radar processing ability is low due to the adoption of a low-cost commercial radar in the ship. Therefore, it is easy for the operator to determine whether the shot is hit or not, the probability of wrong recognition can be reduced, and the radar's resources can be obtained more effectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7B
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• pp.1001-1008
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• 2010

In this paper, we propose the dynamic spectrum allocation (DSA) algorithm using spectrum sharing method considering the long-term priority between NOs and service classes for the maritime communication system environment where a ship locates at either near shore (or land) or off-shore. It was shown that the proposed algorithm using spectrum sharing with priorities could deliver better satisfaction ratio (SR) than the fixed allocation schemes, in the context of provision of required bandwidth (or spectrum) for each users. Therefore, we conclude that the proposed DSA with priorities could apply to the maritime communication environment and exploit the under-used (or unused, idle) spectrum of terrestrial communication networks.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.5
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• pp.645-661
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• 2012

Recently, pirates are infesting on the sea and they have been hijacking the several vessels for example Samho Dream and Samho Jewelry of Korea. One of the items to reduce the risk is to adopt the invader detection system. If the pirates break in to the ship, the detection system can monitor the pirates and then call the security alarm. The crew can gain time to hide to the safe room and the report can be automatically sent to the control room to cope with the situation. For the invader detection, an unmanned observation system was proposed using the image detection algorithm that extracts the invader image from the recording image. To detect the motion area, the difference value was calculated between the current image and the prior image of the invader, and the 'AND' operator was used in calculated image and edge line. The image noise was reduced based on the morphology operation and then the image was transformed into morphological information. Finally, a neural network model was applied to recognize the invader. In the experimental results, it was confirmed that the proposed approach can improve the performance of the recognition in the invader monitoring system.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.261-267
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• 2015

A support system which allows operator to check the condition of a vessel and to warn the sea risk in order to prevent accidents of leisure boats, is required. Therefore, this paper proposes a navigational safety support system to ensure the safety of vessels by monitoring and managing the status of those ships. In developing a system process, each developed equipment is integrated and verified whether the functional, compositional and operational algorithms are working properly according to the designed object.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.42
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• pp.189-210
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• 2009

The United Nations General Assembly adopted the United Nations Convention on Contracts for the International Carriage of Goods Wholly or Partly by Sea(hereinafter referred to as "The Rotterdam Rules") on 11 December 2008. Rotterdam Rules aims to create a contemporary and uniform law providing for modern door-to-door container transport including an international sea leg. but not limited to port-to port carriage of goods. The structure of the liability regime in Rotterdam Rules are globally close to that of the Hague-Visby Rule even though it differs from that of the Hague-Visby Rules in some significant aspects. The Rotterdam Rules are very long. Therefore the Rotterdam Rules will be difficult to understand for even the skilled ship operator or owner or charterer or shipper or consignee or receiver because they are so complicated. This paper only seeks to highlight the salient features of the liability and limitation of liability regime under the Rotterdam Rules. It is expected that the harmonization and modernization of the international legal regime. coupled with the bold attempt to balance the carrier and cargo interests should lead to an overall reduction in transaction costs. increased predictability and greater commercial confidence for international business transactions.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.58
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• pp.287-311
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• 2013

In this study, the scope of previous logistics security were focused only on port and ship. Because of it now extends to the overall (export and import) supply chain areas and in regards with supply security programs in the international level, it reviewed supply chain security programs categorized them into 'ships and port security system', 'container screening system', 'logistics chain authorization system' which are expanded to be adopted in the international level. The major features of those programs are summarized as in building risk management system, providing information ahead, selectivity test and benefits to AEO authorized companies in the customs administration level. The government and companies which are to ensure supply chain security and trade facilitation in order to cope actively with international customs administrative atmosphere need to do the followings : First, they need to build an intra-government integrated supply chain security and make efforts to conclude AEO MRA in order to increase trade competitiveness among major trading countries. Second, they need to build supply chain risk management system in order to enhance management performance through overseas market and company level strategy to obtain and maintain AEO authorization in the company level.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.484-493
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• 2006

Recently, direct load analysis using ship motion program is required to confirm structural safety for the Post-Panamax class large container carrier. However, there is no exact comparative study data for structural response between 20 and 30 wave load. So, in this paper, to compare the hull girder stress response between 20 versus 3D wave load calculation method, direct load analysis and global F.E analysis have been performed for three kinds of large container vessels using each 20 and 30 wave load calculation program. The results of 2D wave load RAO(Response Amplitude Operator) of each dominant load parameter(vertical, torsional and horizontal moment) are generally bigger than that of 30 results, especially in vertical wave bending moment. And the results of structural analysis based on the equivalent design wave method shows that there is a big difference in view of stress, but the stress distribution is very similar for each wave load case.