• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.2
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• pp.228-239
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• 1992

The purpose of the present research is to develop an efficient numerical method for the calculation of potential flow and predict the wave-making resistance for the application to ship design of tuna purse seiner. The paper deals with the numerical calculation of potential flow around the series 60 with forward velocity by the new slender ship theory. This new slender ship theory is based on the asymptotic expression of the Kelvin-source, distributed over the small matrix at each transverse section so as to satisfy the approximate hull boundary condition due to the assumption of slender body. Some numerical results for series 60, C sub(b) =0.6, hull are presented in this paper. The wave pattern and wave resistance are computed at two Froude numbers, 0.267 and 0.304. These results are better than those of Michell's thin ship theory in comparison with measured results. However, it costs much time to compute not only wave resistance but also wave pattern over some range of Froude numbers. More improvements are strongly desired in the numerical procedure.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1601-1604
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• 1998

In this study, the impedance characteristic for wire-prate plused plasma reactor was analyzed by experiment. For this, rotary spark gap and MPC purse generator were used as power source. The reactor impedance decreases with increasing wire length and applied voltage. From this fundamental experiment, we deduced a method for the impedance matching between purse generator and pulsed plasma reactor.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.360-368
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• 1997

Shepherd's purse (Capsella bursa-pastoris) is one of the minor but important vegetable in Korea. The present study records 4 fungal diseases of this plant occurring under natural condition for the first time in Korea. They are white rust caused by Albugo candida, downy mildew by Peronospora parasitica, leaf spot by Pseudocercosporella capsellae, and powdery mildew by Erysiphe cichoracearum of these, white rust and downy mildew were most common causing severe damages and should be managed for the development of greenhouse cultivation of this plant.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.126-126
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• 2017

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.124-126
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• 2005

초고속 통신망 및 이동통신 단말기의 보급을 통해 전자상거래 서비스가 널리 확산되고 있으며, 이로 인해 유.무선 기반의 다양한 전자지불 시스템 및 표준들이 제안되고 있다. 그 중에서도 스마트 카드를 이용한 CESP 전자 상거래 표준이 많이 사용되고 있다. 본 논문에서는 Casper 및 FDR 도구를 사용하여, CEPS 표준 중에서 전자화폐를 이용한 물품 구입 프로토콜을 정형적으로 명세하고, 보안 취약점을 분석해 보았다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.3
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• pp.42-46
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• 1986

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.227-236
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• 1999

Temperal and spacial analysis for catches have been drawing up a catch distribution chart and analysing catches and CPUE(Catch Per Unit Effort) using catch data with purpose of obtaining basic data to establish a selective method of effective fishing the tuna purse seine fishing ground.The temperature profile section and catch was surveyed to analyse the effect of catch in relation to the fishing ground environment.The results are as follows ;1. As for the catch variation between 1983 and 1984, the catch mainly took place on150^{\circ}E$, and after that it moved eastward enlarging the range of catch. In the monthly catch variation between January and February, the catches mainly happened on 135$^{\circ}$~ 150$^{\circ}$E, and then moved to the gradually westward. However, from July it moved to the South and from October Southeast.2. As to the eatch ratio for the school associated with the drifted object, the pelagic migrating school and the school associated with the biological objects, the catch ratio for the school associated with the drift objects was the highest. The catch ratio for the school associated with the drifted object was high in June, July and November whiles between January and March for the pelagic migrating school.3. SST(Sea Surface Temperature) was around 28~29^C$ on the observing line of 137^{\circ}E$ and the catches took place in the north equatorial counter-current situated on around $5^{\circ}~6^{\circ}N$. SST in the northern summer was 1^C$higher than winter and it was about 29~30^C$. The catch happened with the center of north equatorial counter-current. The reason why the catch mainly took place on the north equatorial counter-current is that main catch of tuna purse seine was the school associated with drift objects. It is thought that the fishing grounds are made in waters that have many drift objects like drift logs from the coast.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.369-389
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• 2011

Changes in ecosystem risks were evaluated using the ecosystem-based fisheries assessment (EBFA) approach of Zhang et al. (2009, 2010) and the comprehensive ecosystem-based fisheries management (EBFM) plan was made for the southern sea of Korea in this study. The risk assessment of the southern sea ecosystem was conducted by establishing ecosystem management objectives and by estimating risk scores (RS) for indicators. To conduct this analysis a number of indicators and their reference points for assessing these risk scores were developed in this study. The number of indicators in the risk analysis was 28 for the quantitative tier 1 analysis and 30 for the qualitative tier 2 analysis. The objective risk index (ORI), species risk index (SRI) and fisheries risk index (FRI) were calculated from the risk scores. Comparing the past (1988) and the current (2008) status of fisheries resources, management implications were discussed. The fishery risk index (FRI) of large purse seine fishery in the southern sea of Korea decreased substantially from 0.972 in 1988 to 0.883 in 2008, and improvement in the management of fisheries operated in the southern sea of Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.164-179
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• 2001

Spatio-temporal variation in species composition, abundance and distribution of fisheries resources caught by large purse seine off Korea from 1991 to 1994 was analysed. Out of 19 species, Scomber japonicus (54.7%), Sardinops melanostictus (20.4%), Trachurus japonicus (9.1%), and Scomberomorus niphonius (6.2%) were predominated in catch. These 4 pelagic fishes occupied 90% of total catch. Major pelagic fishes caught by large purse seine were dispersed to northward from spring to summer, and migrated to the southern wintering ground during winter. Fishing effort (number of haul) was high in summer, but catch per unit effort showed a peak in winter. The high CPUE in winter seemed to be related to aggregation of the pelagic fish to the wintering ground in the southern sea. After spawning, they were widely dispersed for feeding in warm months.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.147-153
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• 2014

The purpose of this paper is to examine the roll damping characteristics by bilge keels on the fishing vessel. Unlike other degree of freedom motions, roll motion is highly nonlinear. However the quantitative evaluation of roll damping combined with waves is very important for the fishing vessel. To reduce roll motion, roll motion stabilizers such as a bilge keel is used due to easy made and cheap cost rather than anti-rolling tank and fin-stabilizer. Authors paid attention to the shape of bilge keel and waves to grasp the roll damping for the fishing vessel and studied about the difference of tendencies of roll angle following the shapes of bilge keel. The model ship was the offshore large purse seiner and four types of bilge keel were used. The data from the experiments were provided and analyzed to investigate the rolling characteristics of the model ship being affected by the wave height, wave period and bilge keel shape. The results of the study showed that three types of the bilge keel have little effective, but only one has an effect on the roll damping. So bilge keel shape and its attachment method need to be a future study for the practical use in fishing vessel.