• Journal of the Society of Naval Architects of Korea
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• v.56 no.6
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• pp.497-506
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• 2019

Literature survey was conducted on the 2013 Interim Guidelines for determining the minimum propulsion power to maintain the manoeuvrability of ships in adverse conditions. The International Maritime Organization (IMO) Marine Environment Protection Committee (MEPC) documents related with the Guidelines were reviewed. Compatibility of the present Guidelines can be checked by two different levels: (Level 1) minimum power lines assessment and (Level 2) simplified assessment. The IHS (Information Handling Services) sea-web data on the bulk carriers and the tankers, which were built after 2000, were used to examine the Level 1 assessment. KVLCC2 was used to examine the Level 2 assessment. Regarding the Level 2 assessment, effects of the adverse weather conditions, the added resistance due to waves, the wake fractions and the thrust deduction factors were discussed.

• Proceedings of the Korea Society for Simulation Conference
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• 1998.10a
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• pp.46-50
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• 1998

본 연구는 최근에 국내기업의 물류비용절감을 위한 노력의 일환으로 추진되고 있는 적정 물류장비의 선정을 위한 시뮬레이션 모델의 개발이다. 본 연구에서는 제조공장에서 소비자들에게 공급되는 2단계 물류시스템에서 물류재고와 운송수단을 고려하여 최소 물류비용의 운송대안선정을 위한 의사결정을 할 수 있도록 개발하였다. 이를 위하여 2가지의 시뮬레이션모델의 전산프로그램을 개발하고 응용사례를 통하여 출력을 예시하였다.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.525-532
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• 1999

The standardized Korea Next Generation Reactor (KNGR) NSSS has developed in the basis of the ABB-CE System 80+ design concept. In this study, several regulatory requirements for the KNGR shutdown cooling system (SCS) operation are investigated. The purpose of this study is to establish the technical self-reliance for SCS design by supporting fundamental data such as SDCHX effective area and reactor CCW flow rate. Thermal power of KNGR would be increased to about 4,000 $MW_{th}$ in comparison with thermal power 2.825 $MW_{th}$ of UCN 3&4, therefore, SCS design data shall b recalculated by using the KDESCENT Code, which could evaluate cooling capability of SCS. It is found that SCS minimum flow rate is able to remove the primary sensible heat. Reviewing the major components such as heat exchanger, pump, value, and operating procedure, it is concluded as follows.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.666-671
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• 2023

As international environmental regulations on ship emissions are gradually strengthened, interest in electric propulsion and hybrid propulsion ships is increasing, and various solutions are being developed and applied to these ships, especially stabilization of the power system and system efficiency. The direct current distribution system is being applied as a way to increase the power. In addition, verification and testing of safety and performance of marine DC distribution systems is required. As a result of establishing a DC distribution test bed, verifying the performance of the DC distribution (variable speed power generation) system, and analyzing fuel consumption, this study applied a variable speed power generation system that is applied to DC power distribution for ships, and converted the power output from the generator into a rectifier. A system was developed to convert direct current power to connect to the system and monitor and control these devices. Through tests using this DC distribution system, the maximum voltage was 751.5V and the minimum voltage was 731.4V, and the voltage fluctuation rate was 2.7%, confirming that the voltage is stably supplied within 3%, and a variable speed power generation system was installed according to load fluctuations. When applied, it was confirmed through testing that fuel consumption could be reduced by more than 20% depending on the section compared to the existing constant speed power generation system.