• 해양환경안전학회지
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• 제24권6호
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• pp.654-661
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• 2018

본 논문에서는 마리나 항의 상하가 시설 및 장비의 형태를 분석하고 마리나 이용 대상 선박을 기준으로 기 설치된 마리나의 상하가 시설(리프트 피어)과 장비(마린 모바일 리프트)에 대한 분석을 통해 상하가 시설 및 장비의 설치기준을 마련했다. 국내에서 운항중인 선박 총톤수에 따라 요구되는 리프트 피어의 내부 간격은 35톤 선박은 5.50 m, 50톤 선박은 6.20 m이며, 이를 상하가하기 위한 마린 모바일 리프트의 내측 폭은 35톤 선박은 6.10 m, 50톤 선박은 6.80 m가 필요하다. 국내 마리나에 설치된 리프트 피어는 목표한 선박을 인양할 수 있는 곳은 2곳으로 나타났으며, 그 외 다른 마리나의 리프트 피어 내부 간격은 0.35 ~ 0.50 m가량 좁았다. 또한 운용 중인 마린 모바일 리프트 중 목표한 선박을 상하가하기 위해 필요한 내측 폭을 확보한 장비는 2개로 나타났으며, 그 외 마린 모바일 리프트 내측 폭이 0.3 ~ 0.6 m가량 부족했다.

• 한국항해항만학회지
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• 제27권4호
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• pp.359-366
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• 2003

이 논문은 대한민국 해양사고 예보 시스템 (K-MACFOS)을 개발하기 위한 해양사고 수량화 D/B (N-D/B) 구성과 분석에 관하여 기술하였다. K-MACFOS의 주목표는 일기예보와 같이 해양사고의 예측건수와 위험수준을 방송하기 위한 것이다. 해양사고 데이터는 1990년부터 2000년까지 1년간 위도 33oN∼35oN와 경도 124oE∼127oE의 대한민국 서남해안 일대에서 발생한 총 724건을 수집하였고, 14가지 수량화변환 척도를 이용하여 양적 데이터로 변환하였다. 컬러 콘도-맵 가시화를 이용한 통계분석을 통하여 N-D/B의 유효성과 연구대상 해역의 사고특징을 검토하였다. 또한, 올바른 N-D/B 분석과 정확한 해양사고 건수 예측을 위한 최적 적용기간 선정 방법을 제안하였다.

• 해양환경안전학회지
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• 제29권3호
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• pp.270-280
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• 2023

The creation of marine protected areas is an important aspect of marine ecosystem sustainability. However, South Korea has not achieved its Aichi Biodiversity Target to designate 10% of its sea as marine protected by 2020. Local residents have strong opposition to the designation of protected areas in South Korea; there has been little trust in the government since the 1970s, when residents felt that their property rights were being ignored in favor of creating national parks. Here, we present a case where creation of a marine protected area was led by residents of TongYeong City. The success of a participation income project to remove marine debris in the city seems to be an important factor that led to the designation of the marine protected area. The case of TongYeong City is compared with that of nearby Geoje City, where an ecologically important stream has not been designated as a wetland protection area, although a similar participation income project enrolled the city's residents. The comparison provides a tentative assessment of the conditions needed to increase trust among residents. The results suggest that, if the projects are well-designed and well-managed, participation income projects to remove marine debris can be effective in building trust among stakeholders in potential marine protected areas.

• 수산해양기술연구
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• 제51권3호
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• pp.295-301
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• 2015

Target strength (TS) information is an important parameter that estimates the detection, distribution, and abundance of Aurelia aurita. In order to investigate the biological TS of jellyfish, some factors such as size (bell diameter), tilt angle, pulsation, and symbion should be known. In the ex situ TS measurements, the tilt angles and pulsation from synchronized swimming behavior of four live A. aurita (bell diameters in the air: 54.2 ~ 94.2 mm) were measured with the acoustic data at 70 kHz. The reduced target strength (RTS) of A. aurita was found to change ranged from 13.4 ~ 16.5 dB according to the incidence angles from $-30^{\circ}$ to $24^{\circ}$. When the change rate of bell diameter in the water was 0.2, the TS value showed a 7.2 dB change. These results could be utilized as an important data to understand the acoustic characteristic scattering of A. aurita.

• 한국수산과학회지
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• 제43권5호
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• pp.551-556
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• 2010

The large jellyfish Nemopilema nomurai causes serious damage to fisheries, particularly around the seas of Korea and Japan. Decreasing this damage requires knowledge of the distribution and abundance of jellyfish. Acoustic technology using quantitative echosounders is one method of studying the distribution and abundance of jellyfish. Such methods are commonly used worldwide because they have the advantage of providing substantial information about all water layers in a wide area in a short time. However, in order to conduct an acoustic survey, the acoustic characteristics of the target organism must be known. These can be altered by a number of factors, including pulsation, swimming angle, frequency and size. Accordingly, this study determined the variation in target strength according to pulsation of N. nomurai. Data were analyzed for two jellyfish with bell diameters in air of (a) was 32.0 and (b) 25.0 cm. The pulsation cycle of jellyfish (a) was 1.5~2.0 sec and the target strength (TS) cycle was 1.0~2.5 sec, while jellyfish (b) had a pulsation cycle of 1.0~1.5 sec and TS cycle of 1.0~3.0 sec. The variation width of the TS with the change in pulsation was 7.8 dB (-72.4~-64.6 dB) for jellyfish (a) and 10.3 dB (-71.6~-61.3 dB) for jellyfish (b). The variation in bell diameter was about 0.28 and 0.35, respectively. These results confirmed that the variation in bell diameter caused by pulsation is closely related to the variation in TS.

• 수산해양기술연구
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• 제53권2호
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• pp.152-159
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• 2017

Rockfish was a commercially important fish specie in marine ranching areas in Korea. To estimate density and biomass of rockfish using acoustic method, target strength (TS) information is required on the species. This study measured TS dependence on tilt angle and size on 14 live rockfish individuals at 38, 70, and, 120 kHz by ex-situ measurement (tethered method) and acoustic scattering model (Krichhoff ray mode, KRM). The swimbladdered angle ranged from 18 to $30^{\circ}$ ($mean{\pm}s.d.=26{\pm}4^{\circ}$). The mean TS for all individuals was highest -35.9 dB of tilt angle $-17^{\circ}$ at 38 kHz, -35.4 dB of tilt angle $-25^{\circ}$ at 70 kHz, and -34.9 dB of tilt angle $-22^{\circ}$ at 120 kHz. The ex-situ TS-total length (TL, cm) relationships were $TS_{38kHz}=20log_{10}(TL)-67.1$, $TS_{70kHz}=20log_{10}(TL)-68.6$, and $TS_{120kHz}=20log_{10}(TL)-69.9$, respectively. The model TS-total length (TL, cm) relationships were $TS_{38kHz}=20log_{10}(TL)-66.4$, $TS_{70kHz}=20log_{10}(TL)-67.0$, $TS_{120kHz}=20log_{10}(TL)-67.0$. The two measurements between the ex-situ TS and KRM model for TS-tilt angle and fish size were found to be significantly correlated.

• 수산해양기술연구
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• 제49권4호
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• pp.459-468
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• 2013

In the application of the ecosystem-based fisheries assessment Jeonnam marine ranching ecosystem, two fisheries, funnel fishery and trap fishery, were selected as target fisheries. Black seabream, Acanthopagru schlegelii, rock bream, Sebastes inermis, gray mullet, Mugil cephalus, were selected as target species for the funnel fishery, and conger eel, Conger myriaster, was target species for the trap fishery. For assessing indicators of four management objectives, that is the maintenance of sustainability, biodiversity, habitat quality and socio-economic benefits, indicators were selected considering the availability of data, which were 5 indicators for sustainability, 3 indicators for biodiversity, 4 indicators for habitat, 2 indicators for socio-economic benefit. The Objective risk indices for sustainability and biodiversity of two fisheries were estimated at yellow zone, medium risk level. The objective risk indices for habitat and socio-economic benefit were estimated at green zone, safe level. The species risk indices (SRI) were estimated at yellow zone. The fishery risk indices (FRIs) were estimated at 1.143 and 1.400 for funnel net fishery and trap fishery, respectively. Finally the ecosystem risk index estimated at 1.184.

• 한국환경복원기술학회지
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• 제21권3호
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• pp.57-65
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• 2018

The study is conducted to establish the National Protected Areas Integrated System(NPAIS) which includes National Protected Areas(NPAs) and other conservation measures in terms of effective ways for biodiversity conservation. Additionally, it is carried out to evaluate progress toward quantitative expansion goals in Aichi biodiversity Target 11. The NPAIS consists of NPAs and other effective area-based conservation measures(OECMs). There are two different types of OECMs. OECMs type I, including water-source protection Areas(WPA), riparian zones(RZ), fishery-resource protection zones (FPZ), and urban natural park zones(UNPZ), is a potential protected area which is recommended to be incorporated into the NPAs for effective management. OECMs type II means development restriction zones(DRZ), natural recreation forests(NRF), and buffer zones for Korea national arboretum(BKNA). As a result of evaluating the quantitative expansion goals of the NPAIS, terrestrial and inland water protected areas exceed 17% of the quantitative goal in Aichi biodiversity Target 11. The larger the area of individual OECMs and the lower the degree of overlap with NPAs, the higher the contribution of them to the terrestrial and inland water protected areas. DRZ contributes to enlarge more than 3% of quantitative expansion. And RZ and NRF contribute more than 1%. The marine protected areas are expanded by $1,425km^2$ through FPZ, but the expanded area is very small as comparing with the total marine area. It adds only 0.321% to the quantitative expansion. The rest of OECMs also has very poor quantitative expansion contributions in the marine area. Consequently, the NPAIS is effective for quantitative expansion of land areas, but not for marine areas.

• 한국수산과학회지
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• 제37권4호
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• pp.345-353
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• 2004

Target strength (TS) of Japanese common squids (Todarodes pacificus) were measured using 38 and 120 kHz split beam scientific echosounders under the live condition. For the TS measurement of an individual, a total of 3 squids (mantle length (ML): 22.8, 25, and 27 cm) were used using small fishhook method, whereas for measurement of swimming angle, a total of 8 squids (ML: 21-27 cm) were used under live condition, confined with net cage with 2 m diameter At the same time, two underwater video cameras enabled continuous monitoring of squid behavior. Considering normal behavior, the mean TS at 38 and 120 kHz varied from -48.6 to -45.9 dB, and from -46.5 to -44.6 dB, respectively In both frequencies, mean TS at 120 kHz is relatively higher than that of 38 kHz, approximately 1.3-2.5 dB. From free living condition, the mean swimming angle of the squlds was $-24^{\circ}$. The results of the measurement will be provided basic information for conducting acoustic surveys of the squid.

• 수산해양기술연구
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• 제46권2호
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• pp.157-163
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• 2010

The indirect target strength (TS) estimation method which uses the Kirchhoff ray mode model (KRM model) was discussed to apply for a biomass estimation in the water of mixed species. TS of 25 live scorpion fishes for 120kHz were measured by a tethered method and of others dominant 5 species in the marine ranching ground of Jeju coastal water including a scorpion fish were also estimated by KRM model. The measurement TS of scorpion fish well agreed with the theoretical values and the standard formula of scorpion fish was estimated as $TS_{120kHz}=20Log\;(L)-72.9$ ($r^2=0.67$). TScm values estimated on trial to each sample of dominant 5 species were from -69.3dB to -75.1dB at 120kHz and they were in the general range of swimbladdered fish. It was clarified that TS by KRM model can be used to estimate fish biomass estimation by increasing a sample number and is more effective under the condition that there is rare TS information for inhabiting species in mixed-species area.