• Journal of the Society of Naval Architects of Korea
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• v.47 no.4
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• pp.477-486
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• 2010

During sailing by wind-driven thrust on the sail, a catamaran sailing yacht generates leeway and heeling. For predicting sail force, a model test was carried out according to running attitude. Through the model test, drag and side force of the real ship was predicted. A purpose of this study is to find sail force to C.E from changed attitude during running direction. By balance of hull and sail, a heeling force of designed sail is predicted. Also through heeling force and driving force, total sail force and direction from C.E are considered with changed mast including leeway and heeling.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.3
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• pp.321-327
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• 2010

During sailing by wind-driven thrust on the sail, a catamaran sailing yacht generates leeway and heeling. For estimating resistance and moment prediction of a real ship by changing of running attitude, a model test of the ship has to be carried out. This study aims at establishing experimental techniques for a catamaran sailing yacht by changed attitude during running direction. Through the model test, drag and side force of the real ship are predicted. Also through experiment, rolling and yawing moments were considered.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.1 s.139
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• pp.50-56
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• 2005

The performance of Traditional Korean Fishing Boat is surveyed based on Report on Investigation of Korean Fishing Boat. The characteristics of Traditional Korean fishing Boat of hull form, rudder, sail are studied from the view point of modern sailing boat design. As a result we find her hull form is an excellent candidate of mother ship for modern boat design and the great sized rudder of Traditional Korean Fishing Boat makes a role of the centerboard of modern sailing host. And also we find the sail of Traditional Korean fishing Boat is more useful for sailing against the wind direction than an ordinary Lug sail.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.311-318
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• 2004

It is very important for the safe navigation and fishing operation to ensure the hull response of a fishing vessel in rough seas. This is an experimental study on the dynamical characteristics of ship's motion during operating job and sailing in the real sea. The experiments were carried out on the small stern trawler in operating job and sailing, and then the ship's roll and pitch motion were simultaneously recorded by P/C according to the wave directions. From these data, the statistical properties and power spectra were obtained and the analysis of ship's motions in the both case were made. The results obtained are summarized follows : (1) The amplitudes of pitch motion don't appear a big different between trawl job and sailing, but at bow seas, its in sailing have a tendency to increase more than in trawl job. The amplitudes of roll motion appear a bog different between trawl job and sailing, but at beam sea, that slightly decreasing tendency. (2) The peak period of pitch motion in trawl job and sailing change, but that of roll motion don't change according to the direction of waves. (3) The warp tention cause the motion of hull to be reduce, if the tention of each side have a ballance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.65-68
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• 2009

A Nautical Publication is a special purpose book, or a specially compiled database, that is issued officially by or on the authority of a Government, authorized Hydrographic Office or other elevant ogvernment institution and is designed to meet the requirements of marine navigation Nautical publications include list of lights, Buoys, Beacons, Radio Siganals, Sailing directions. The SNPWG(Standardization Nautical Publications Working Group) from the IHO is working to implement in computer systems all those elements of interest for Hydrography and Navigation Concerning the nautical publications digitization process, the SNPWG has defined three types of nautical publication: Type 1 : Hard copy(NP1), Type 2 : Digital version, A slight modification of type 1(NP2), Type 3 : Digital version for ECDIS(NP3). Nautical Publication is essential with nautical charts as refrerence information to navigation. Development of digital nautical publication is needed for liaison with charts production system, up-to-dateness of hydrographic information, improvement of service. But, korea's status is positioned in NP1. In our study, we surveyed the present status of nautical publciation for strategy of digital nautical publication development. Also, we build database of south coast of sailing direction and develp a program for compilation and management of sailing direction.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.1
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• pp.93-98
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• 2012

In this study, we introduced image processing technic to measure shape variations of general bodies and applied it to the flexible yacht sail. Shape measurements of simple bodies sails were carried out and results showed that technic can be a reliable method to measure shape variations of the flexible yacht sail. The sail shape variation of 30ft sloop type yacht sail is measured on different sailing conditions. As velocity and direction of wind are increased, trailing edges in the upper part of the sail become more open than the lower part of the sail which are not changed. So it is confirmed that the shape measurement of a sail shape depending on a sailing condition is possible to use image processing scheme.

• Journal of Navigation and Port Research
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• v.36 no.8
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• pp.619-624
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• 2012

In 1969, Y.J. Yun wrote the terrestrial navigation text book that discussed earth sciences, aides to navigation, chart and publications, tide and tidal current, piloting, rhumb-line sailing, great circle sailing grounded on the hand-on background and theory. It has still been used as a principle text book in a lot of maritime academies and schools. And many contents and definitions came from other terrestrial navigation books published in the United States of America, the United Kingdom, and Japan. But some of them have caused the misunderstanding because they had no enough explanation and explained by incorrect items. In this study, we have found out the problems in the terms course and heading which are related with the direction of the vessel movement, and proposed the amended definitions in order to prevent the misunderstanding and confusion. of them.

• Journal of Advanced Research in Ocean Engineering
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• v.4 no.2
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• pp.53-65
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• 2018

The load condition significantly influences ship maneuverability in calm water. In this research, the effect of the load condition on turning performance of a very large crude oil carrier (VLCC) sailing in adverse weather conditions is investigated by an MMG-based maneuvering simulation method. The relative drift direction of the ship in turning to the wave direction is $20^{\circ}-30^{\circ}$ in ballast load condition (NB) and full load condition (DF) with a rudder angle $35^{\circ}$ and almost constant for any wind (wave) directions. The drifting displacement in turning under NB becomes larger than that under DF at the same environmental condition. Advance $A_d$ and tactical diameter $D_t$ become significantly small with an increasing Beaufort scale in head wind and waves when approaching, although $A_d$ and $D_t$ are almost constant in following wind and waves. In beam wind and waves, the tendency depends on the plus and minus of the rudder angle.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.49
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• pp.213-236
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• 2011

Korea Shipping Act admits shipping conferences' joint actions like rate agreement, sailing agreement in some degree for development of shipping transport industries for decades. Meanwhile, EU has prohibited all kinds of shipping conferences' joint actions since October 2008, and many advanced countries also have similar position on shipping conference. The balance development between shippers and ship owners is very important in terms of national economic growth. So it is appropriate time to revise related laws such as Shipping Act and Monopoly Regulation and Fair Trade Act. First, It is direction for revision of Korean Shipping Act. The act has to define precisely the criteria of "unfairness" in case of admitting of shipping conferences' joint actions. Shipping conferences have a conference with shipper or shipper's delegation substantially on freight and transport conditions and so on. Second, It is direction for revision of Monopoly Regulation and Fair Trade Act. The fair trade commission has to perform fair roles between shippers and ship owners. The judgement of fairness has to confirm according to the spirit of not Korea Shipping Act but Korea Monopoly Regulation and Fair Trade Act itself.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.3
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• pp.198-204
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• 2014

Ships sailing the seas encounter air resistance. The air resistance depends on the shape of the above-water hull, the ship speed, the wind speed and wind direction. The experimental or statistical methods which are used to predict the air resistance are one of the essential procedures of the calculation of the towing force of the disabled ships. This paper shows simplified air resistance prediction method using the variables of the projected area of the above-water hull, the speed of the ship, the wind speed and its direction. These methods have been applied to the existing computer program which had been set up to predict the towing force of the disabled ships.