• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.305-312
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• 2023

Diet composition and feeding strategy of the largehead hairtail, Trichiurus japonicas were studied using 375 specimens collected by purse seine, set net fisheries and lure fishing from February 2021 to January 2022 in the southern sea of Korea. The anal length (AL) of these specimens was from 3.4~49.0 cm. T. japonicus fed majorly on Fishes (especially Engraulis japonicus) based on ranking index (%RI=99.3). Fishes were the main prey items for all size classes. T. japonicas also showed size-related dietary shift from E. japonicus to T. japonicus, Larimichthys polyactis and Engraulidae. Fishes were the main prey items for all seasons. The main fish prey during spring and summer was E. japonicus, but in the autumn and winter, the E. japonicus portion decreased, and T. japonicus, L. polyactis, and Engraulidae portion increased. T. japonicus were specialized feeders with E. japonicus as their dominant prey.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.5-9
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• 2003

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.714-720
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• 2022

A dietary comparison of yellow goosefish Lophius litulon in the South Sea and Yellow Sea was performed by analyzing stomach contents. Using a bottom trawl net from fisheries resources survey vessels of the National Institute of Fisheries Science, 326 individuals were collected from the South Sea and 166 individuals were collected from the Yellow Sea. The total length range of L. litulon was 5.3-68.4 cm for individuals collected from the South Sea and 7.5-55.1 cm for individuals collected from the Yellow Sea. Based on the index of relative importance and the variation in stomach contents by fish size, L. litulon was found to be a piscevore and a spatiotemporally opportunistic feeder fish that fed mainly on pisces. There were differences in the composition of the stomach contents by season, location, and the interaction between the season and the location. Thus, the diet of L. litulon is affected by the prey abundance and prey spectrum of the habitat.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.129-135
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• 2023

The diet composition of skinnycheek lanternfish, Benthosema pterotum were collected by bottom trawl net in the South Sea of Korea during 2021 (February, May, August, and November) and 2022 (February, April, August, and November). The size of the specimens ranged from 16 to 73 mm in total length. B. pterotum were mesopelagic carnivores that mainly consumed euphausiids and copepods. Its diets included small quantities of amphipods, shrimps, mysids, etc. We calculated the trophic level as 3.16 for B. pterotum. The individuals of small size class (<40 mm) fed mainly on copepods. In the next size classes (40~45 mm, 45~50 mm, 50~55 mm), copepods' proportion decreased and euphausiids increased. In the largest class (55~60 mm and ≥60 mm), the proportion of euphausiids' decreased, and shrimps increased. As the body size of B. pterotum increased the mean weight of prey per stomach (mW/ST) tended to significantly increase (One-way ANOVA, P<0.05).

• Korean Journal of Ichthyology
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• v.35 no.3
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• pp.177-182
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• 2023

Total 158 Conger myriaster were examined and the range of Preanal length (PaL) was 8.2~40.1 cm and average Preanal length was 17.3 cm. Proportion of the empty stomach was 30.4% and individuals, which the prey items were found in stomach, were 110. The most important prey component in the diets of C. myriaster was Pisces that constituted 54.4% in %IRI (Index of relative importance). Engraulis japonicus was the most important prey component in Pisces. Macrura was the second largest prey component and Crangon hakodatei was the most important prey component in Macrura. The result of analysis in ontogenetic changes significantly exhibited among three size classes (<15.0 cm, 15.0~20.0 cm, ≥20.0 cm). The proportion of Macrura decreased as increasing body size, whereas the consumption of Pisces increased gradually. As body size of C. myriaster increased, the mean weight of prey per stomach (mW/ST) increased (one way-ANOVA, P<0.05).

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.203-204
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• 2000

80년대 초부터 시작된 대하 양식은 양식 생산량이 연간 2천톤 이상 달하여 우리나라 주요 양식 산업으로 자리잡아 가고 있으며, 특히 서해안은 광활한 갯벌과 폐염전, 유휴 농경지의 이용 등 지형적으로 대하 양식에 매우 유리한 조건을 갖추고 있어 해마다 양식면적과 양식장의 수가 꾸준히 증가하고 있는 추세이다. 그러나 지속되는 양식활동과 양식장의 적정 수용능력을 초과하는 과밀양식으로 인하여 양식장의 노화와 환경악화가 가속화됨으로써 각종 세균성 및 바이러스성 질병이 빈번하게 발생하여 양식어업인에게 큰 피해를 입히고 있는 실정이다. (중략)

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.200-200
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• 2018

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.146-147
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• 2000

해양에서 입자유기물질은 생태계 내 먹이망의 중요한 요소로서 작용한다. 입자유기 물질이 생태계 내 먹이망의 에너지원으로 전환, 이용될 때 그러한 물질과 에너지 흐름 경로를 이해하기 위해서는 이들 물질의 구성 요소에 대한 지식이 필요하다. 본 연구에서는 서로 다른 지형구조와 양식대상 생물을 가지는 여러 내만의 양식 환경을 이해하기 위하여 일차적으로 한반도 남해의 대표적인 이매패류 양식해역 3개 해역에 대한 입자유기물질의 분포와 조성을 조사ㆍ비교하였다. (중략)

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.3
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• pp.369-376
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• 2014

Recent climate change and ensure each country's marine fisheries resources due to the sharp decline to address the eco-friendly farming has emerged. Marine aquaculture operations to provide ease of use for the fishing ship cranes. In this paper, we use the default handler for the shipping cranes and improve the working environment of the received video equipment in the work area through the monitoring and analysis of visual information to optimize the image, convenient and high visibility for workers to have real-time video guide system is proposed.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1401-1411
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• 2023

In the face of escalating utilization of the marine spatial domain, conflicts have emerged among stakeholders, necessitating effective management strategies beyond conventional government permits and regulations. Particularly within the domain of aquaculture, operational oversight relies on a localized licensing system, posing challenges in accurately assessing the prevailing circumstances. This research employs synthetic aperture radar (SAR) imagery as a tool to monitor coastal aquaculture fish farms, aimed at enhancing insights into management protocols. Leveraging Sentinel-1A imagery and time series SAR data integration, a superimposition technique is utilized, facilitating noise reduction while retaining crucial information regarding smaller-scale facilities, such as fish farms. Through analysis of VH polarization data, a detection overall accuracy of approximately 88% for coastal fish farms was achieved. The findings of this study offer potential applications in the continuous monitoring of aquaculture farms in correspondence with seasonal variations in aquaculture yields, thereby proposing frameworks for the establishment of effective management cycles for marine space utilization.