• 대한조선학회논문집
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• 제56권5호
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• pp.447-456
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• 2019

In the early stage of ship design, the rapid prediction of resistance of hull forms is required. Although there are more accurate prediction methods such as model test and CFD analysis, statistical methods are still widely used because of their cost-effectiveness and quickness in producing the results. This study suggests the prediction formula for the residual resistance coefficient (Cr) of the low-speed full ships. The formula was derived from the statistical analysis of model test results in KRISO database. In order to improve prediction accuracy, the local variables of hull forms are defined and used for the regression process. The regression formula for these variables using only principal dimensions of hull forms are also provided.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1997년도 Proceedings of KIN-CIN Joint Symposium 97 on Safety of Shipping and History of Maritime Communication between Korea and China around 9th Century
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• pp.185-202
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• 1997

Hull forms of ancient ships in Korea and China have been changed according to their voyages and routes. Therefore it is necessary for shipbuilding engineers to reestablish the ancient shipbuilding history, and to presume, restore and revive the lost cultural inheritances. We, however, do not have many historical documents or credible materials that can our ancestors' great shipbuilding techniques : at the same time we do not have paid much attention to the research on such documents and materials. This paper aims not only to study and compare shifting process of ancient ship's hull forms in Korea and China by making use of verifiable materials obtained in the process of excavating and restoring Shinan ancient ship. The results of comparing structural characteristics and hull forms of ancient ships in Korea and China and as follwing : (1) Korean ancient ships have transverse beam instead of frame . Judged from the bottomform, Korean ancient ships are grooved clinker type ships of flat bottom type, in which bottom planking is fixed by wooden bar. (2) Chinese ancient ships have transverse bulkhead structure instead of frame, Judged from the bottom form , Chinese ancient ships are rabetted clinker type ships of V-bottom type with a bar keel. The form , the position, and the size of a sail are closely related with the wind force. It is not only quite difficult to presume forms and sizes of ancient ships' sails precisely, but also impossible to come to an accurate conclusion wihtout much experience. Current 10-year-statistics of the wind force are used to obtain presumed routes of ancient ships in Korea and China. Conclusions obtained from the hull form , sail form and size , and mast height of Shinan ancient ship will provide credible data for sea trade routes and transformation capability, and wil be used for effective materials on the study of the shifting process of ancient ships in Korea and China.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1998년도 춘계학술발표회 논문집
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• pp.83-89
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• 1998

In case of Radar Simulator ,the target ships should be generated and displayed on the monitor to provide the trainee with the feeling of real situation. The scenario methodology, which has been developed and used in Korea so far, however, has a fixed scenario, in which target ships are generated in the same manner at all time. As a result, the Radar simulator developed in Korea so far was in lack of training efficiency, as the trainee can get earily familiarized with the fixed scenaio. The paper, therefore, suggests the target ship generating methodology using random variables to improve the training efficiency of the existing simulator. In generating the target ships using this methodology, the speed, distance between the ships , and time interval of ships and time of ships were considered as a major factors which dterminie the ship's movements. The new methodology suggested was examined and found to generate target ships successfully giving a trainee the feeling of real situation.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1997년도 Proceedings of KIN-CIN Joint Symposium 97 on Safety of Shipping and History of Maritime Communication between Korea and China around 9th Century
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• pp.223-233
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• 1997

The paper is a comparative study of the 9th -century Chinese, Korean and Japanese ships. It discusses the professional level of ship-bulding, the functions of ships, the routes of the ships, and the economic and cultural exchanges between China and Korea. In addition, it also introduces the history of the Xinluos living in China focuses on the distinction between Xinluo Guan, Xinluo Suo and Xinluo Fang, which is often confused in the Chinese, Korean and Japanese academic world.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.194-196
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• 2003

• 한국정보통신학회논문지
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• 제3권4호
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• pp.805-817
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• 1999

In this paper, the needs for introduction and adoption of MㆍHF DSC/NBDP system and for developments of its circuits and call sequences for use in the maritime mobile services for small-ships, leisure-ships and fishing ships are analyzed, discussed. Also design and implement for MㆍHF(1.6-4MHz) DSC/NBDP system is discussed. Most of casualties have been arisen from small-ships and fishing ships during last 5 years. So, the SAR schematic plans should been prepared to prevent casualties and facilitate the activities of SAR for those ships. DSC/NBDP for MㆍHF system is able to fulfill the roles of efficient SAR communication functions, and to advance the SAR system to small ships and fishing ships. This study is focused on the techniques of processing the DSC call sequences and the ARQ sequences of NBDP system. Especially ARQ sequences are expanded into processing of Korean letters, designed the call sequences and code conversion algorithm for Korean-code. It will be evaluated the availability of Korean-NBDP system. In designing the Transmitting circuits and Receiving circuits, for the carrier generation, DDS(Direct Digital Synthesizer) is used in stead of the Phase Locked Loop and frequency conversion by the mixer, BPF. And PSK modulation signals are directly generated by the controls of DDS, which show the characteristics of Spurious Free Dynamic Range are below -62dBc. Also, the monolithic U subsystem IC which provides various functional components, AD608 is used for designing the receiving circuitsㆍAnd the algorithm of Phasing methode for FSK demodulation are devised to process IF frequency 455kHz in the IF circuits.

• 한국항해항만학회지
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• 제28권5호
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• pp.413-420
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• 2004

건설중인 부산신항이 2011년에 개장하게 되면 해상교통량의 증가 및 12,000TEU급 포대형 컨테이너선의 입ㆍ출항이 예상되고 있다. 따라서 해상통량의 증가 및 초대형 선박의 안전한 입ㆍ출항이 고려된 새로운 항로의 배치가 이루어져야 할 것으로 판단된다. 이 연구에서는 부산신항의 새로운 항로배치의 제안을 위해 해상상황, 해상교통 및 선행연구를 조사하였고 전문가 의견법 및 델파이법을 이용하여 항로배치안을 선정하였으며 그 적정성 여부의 검증을 위해 국내외 항로지침과의 비교ㆍ분석 및 시뮬레이션 검토를 실시하였다.

• 한국항공운항학회지
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• 제29권3호
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• pp.24-33
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• 2021

Although it is the first transportation method to apply the 'Ground Effect' applied to aircraft to ships, WIG ships, which are classified as 'Ships' operating on the water under international law. The pilot aptitude test, which has the effect of preventing safety accidents in advance, has not yet been established as a legal system in S. Korea, after being certified by the Korean Register of Shipping (KR) for the first time in the world in March 2020. Therefore, the purpose of this study is to ensure that identifying the importance, recognition, correlation, etc. of the tools and items of aptitude testing, from a group of experts, can be used appropriately for future development of legal aptitude testing tools. As a method of study, the questionnaire method was used, and the analysis confirmed that the tools used on aircraft and ships could be used appropriately. In particular, Due to the characteristics of the WIG ships, it was confirmed that it is necessary to develop more specifically in the future, the operational qualifications and physical fitness items, which are the aptitude evaluation items.

• 한국해양공학회지
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• 제35권2호
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• pp.150-160
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• 2021

To ensure the international competitiveness of the domestic offshore plant industry, a consensus has been formed regarding the requirement for large offshore basins for performing offshore plant performance verification. Accordingly, the Korea Research Institute of Ships & Ocean Engineering has built the world's largest deep ocean engineering basin (DOEB). The purpose of this study is to evaluate the characteristics of velocity distribution under various conditions of the DOEB. An independent measuring jig is designed and manufactured to measure the current velocities of many locations within a short time. The measurement jig is a 15-m-high triangular-truss structure, and the measurement sensors can move 15 m vertically through an electric motor-wire device. The current speed is measured under various impeller revolutions per minute and locations of the DOEB using the jig. The spatial distribution characteristics of the current velocity in the DOEB and the performance of the current generator are analyzed. The maximum speed is 0.56 m/s in the center of the DOEB water surface, thereby confirming sufficient current velocity distribution uniformity for model testing.

• 해양환경안전학회지
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• 제29권3호
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• pp.288-295
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• 2023

The purpose of this study is to evaluate the feasibility of the new marine leisure ships. In order to achieve the research purpose, the cost and income were calculated based on the operating of other marine leisure ships, and the feasibility of the project was empirically analyzed. This study established a research model that applies the values derived by empirically analyzing ships with similar specifications, to the new marine leisure ships. We then calculated the cost-benefit analysis, net present value, and internal return, and evaluated the feasibility of the project based on this. As a result of the business feasibility analysis of investing in marine leisure ship, it was found that economic feasibility exists with a B/C of 1.042 and 1.049 for new and secondhand ships, respectively; however, considering the stability of the ship and the publicity and continuity of the business operation, it is recommended to invest in new ships compared to secondhand ships. The total benefit over the 10-year operating period using a social discount rate of 4.5% was evaluated to be about KRW 292.0 billion, which is higher than the total cost of KRW 256.6 billion. In conclusion, the profitability analysis showed that the B/C was 1.042, the NPV was KRW 193 billion, and the IRR was 2.1%, which indicates that profitability is weakly secured.