• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.185-189
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• 2001

A study on the new active circulation type oil-water separation system including buoyancy type guidance system was carried out in this paper. Oil-water separation system is composed of several oil separation steps. Buoy type oil guiding system was developed based on the difference of buoyance of water and oil. The design speed of this vessel is 25 knots.

• Journal of Ocean Engineering and Technology
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• v.20 no.1 s.68
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• pp.32-36
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• 2006

The initial hull form of a 100 tan, 45 knot class high-speed craft is newly developed. The resistance performances are investigated using a model test at high speed in a circulating water channel. The effect of the initial trim is studied together. Wave patterns are observed to clarify the relationship between the resistance performance and the wave characteristics. It can be found that the initial trim plays a role in increasing the resistance performance above a certain velocity.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.1
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• pp.116-124
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• 2006

A model test was carried out, in order to verify the hydrodynamic performances of public 30 feet class sailing yacht. In the initial design stage, the performances and the running attitude of sail yacht including the hull form and sail plan, appendages were estimated by VPP, from which made the representative test conditions. A new experiment system such as captive model device was composed because the running attitude could be changed by wind conditions. The test results show that the minimum resistance is generated in the heeling 20 degree. which was expected in the initial design stage. It is thought to be the useful informations that the keel has an effects on hydrodynamic forces and resistance differences between the upwind and the downwind condition. Also this paper is associated with the state-of-the-art of calculating sailing yacht performance as this is performed in velocity Prediction program (VPP) The VPP results shows a typical shape of a sailing yacht and the designed yacht has the best performance at 120 degree angle of true wind with 20 knots.

• Journal of the Korea Furniture Society
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• v.19 no.2
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• pp.106-110
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• 2008

This paper investigated and validated the mechanisms and principles for constructing reticular structure of plant fiber through frothing solution approach. After process, plant fibers became low-density reticular-structured block with all properties meeting Chinese standards for cushion packing materials. The bonds between fibers acted as knots in a truss and were strong enough to keep space occupied by bubbles in the frothing solution from shrinking in the subsequent draining process. The formation of the reticular structure depends mainly on the pressure difference between inside and outside bubble, the effect of surface adsorbent force on bubble film, and hydrogen bond among fiber hydroxide.

• Bulletin of the Korean Mathematical Society
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• v.49 no.2
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• pp.395-409
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• 2012

In the study of homology cobordisms, knot concordance and link concordance, the following technical problem arises frequently: let ${\pi}$ be a group and let M ${\rightarrow}$ N be a homomorphism between projective $\mathbb{Z}[{\pi}]$-modules such that $\mathbb{Z}_p\;{\otimes}_{\mathbb{Z}[{\pi}]}M{\rightarrow}\mathbb{Z}_p{\otimes}_{\mathbb{Z}[{\pi}]}\;N$ is injective; for which other right $\mathbb{Z}[{\pi}]$-modules V is the induced map $V{\otimes}_{\mathbb{Z}[{\pi}]}\;M{\rightarrow}\;V{\otimes}_{\mathbb{Z}[{\pi}]}\;N$ also injective? Our main theorem gives a new criterion which combines and generalizes many previous results.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.141-144
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• 2006

The tidal pi lot plant is being built in the Uldolmok waterway using Its strong tidal current with maximum current of about 12knots, which is revealed from the first direct observation using ADCP, on February, 2002. a serious of field observations (for example, ADCP observation was tarried out both at February 2002 and September, 2003), along with numerical modeling, have been carried out over the last several years, in order to understand the tidal dynamics and to examine the related variables according to the tidal current power plant (TCPP) operation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.2
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• pp.113-121
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• 2005

How to extimate the angle of attack of a vertical V-type cambered otter board was described. A three-dimensional semi-analytic treatment of a towing cable system was applied to the field experiments of a midwater trawl obtained by the Scanmar system. Also the equilibrium condition of the horizontal component and vertical component of forces and moment around the otter board was used. When the warp length was 300m long and the towing speed was between 2.61 and 3.86 knots, the estimated angle of attack of the otter board was ranged between $24.7^{\circ}$ and $26.2^{\circ}$, though the maximum lift force was at the angle of attack $22^{\circ}$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.68-74
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• 2008

This study is concerned with the development of the basic planing hull form of small fishing boat in 25 knots high speed. A series of model test to determine the optimum performance hull form of actual fishing boat with 10 gross tonnage was carried out for 5 models made available planing hull form in the circulation water channel. Model test was performed with the resistance test to study the hydrodynamic characteristics of model ships and the sinkage and trim measurement to investigate the stability of model ships and also the wave pattern observation to analyze the effectiveness of model ships. As the result, the planing hull form of P-4 with deep V type bow can be derived as the best hull form with good performance especially in ship's resistance efficiency showing less residual resistance and sinkage and trim and the spray effect, etc..

• KCID journal
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• v.18 no.2
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• pp.76-86
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• 2011

This study was conducted to clarify community characteristics of waterbirds migrating to Seamangum area from 2002 to 2009. Total maximum count of waterbirds observed at Saemangum area was 686,337 individuals of 176 species. 158 species and 548,989 individuals were recorded on Mangyung Estuary and 158 species and 213,794 individuals were recorded on Dongjin Estuary. Dominance species were Baikal Teals Anas formosa (40.80%), Great Knots Calidris tenuirostris (18.03%), Mallards Anas platyrhynchos (11.67%) and Dunlins Calidris alpina(6.02%). Shorerbirds were declined and waterfowl were increased during survey periods. Natural monuments and endangered birds were 27 species.

• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.337-343
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• 2012

The Korean bottom trawl survey was conducted using a trawl designed by the National Fisheries Research and Development Institute (NFRDI). The capture efficiency and size selectivity of this trawl for snow crab Chionoecetes opilio was investigated by experimental tows. An auxiliary sampling net (underbag) was attached beneath the trawl net to capture crabs escaping under the trawl footrope. Experimental tows were made by the same vessel speed (3.4 knots) as in the bottom trawl survey, but toing time was shortened from the standard 30 min to 10 min to reduce possible trawl distortion due to the high catch rate of mud and debris in the underbag. In averaged over 17 tows conducted between 110-383 m depth, trawl efficiency of both males and females combined increased from about 10% at 20 mm (carapace width) to about 70% at 100 mm, with a width of 50% capture equal to 78 mm.