• 대한조선학회논문집
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• 제58권1호
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• pp.32-39
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• 2021

Korean coastal fishery suffers from profitability degradation due to a decrease in fisheries resources, pollution in coastal waters, fuel coast increase, and market opening for aquaculture products. The next generation Korean fishing vessel aims at the improvement of energy efficiency, enhancement of crew welfare, and safety. These purposes can be accomplished by adopting a new standard hull form with improved resistance performance and a modernized residence facility on the deck. In order to improve resistance performance, this study attempts to optimize design variables for stern flaps for three kinds of fishing vessels - coastal multi-purpose, coastal trap, and dredged nets. A series of model tests for these fishing vessels was carried out in the towing tank of Pusan National University. The results indicate that for some cases, the stern flap caused the stern trim of the vessel to decrease, leading to the resistance reduction.

• 수산해양교육연구
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• 제27권4호
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• pp.1129-1135
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• 2015

The stow net is a stationary gear made from netting, usually in shape like trawl net without wings. The nets are fixed by means of anchors, placed according to the direction and strength of the current. And the commercial fishing is associated with high rate of fatal and non-fatal occupational injury. The hazard factors analysis for the fishermen's safety of offshore stow nets vessel was conducted to serve as a basic data for improving the healthy and safe working environment of fishermen using fishermen's occupational accidents of the national federation of fisheries cooperatives (NFFC) from 2012 to 2014 (n=1,144). As a result, the average occupational accident occurrence rate of this fishery was 206.9‰ in all industries 36.9 times the rate of that. In addition, average death and missing rate was found to have a very serious level management to 50.4‰ in all industries of death of 42.0 times. The accident occurred in 84.5 to 94.6% was happened at sea. The struck by object, slipping, contact with machinery, contact by object or gear and others occurred more frequently in order on the frequency of accident occurrence pattern. However, the occurrence rate of death and missing did not match the frequency of accident pattern. In other words, slipping occurred frequently higher while death and missing risk was not high. And the contact with fishing gear and fall in the waters was low while death and missing risk was high. The results are expected to contribute for identification and assessment of safety hazard occurred in offshore stow nets vessel.

• Ocean and Polar Research
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• 제41권4호
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• pp.311-318
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• 2019

We analyzed the preliminary survey data (2014-2016) of macrobenthic community biomass (n = 112) from the wind farm area located in the southern part of the west coast of Korea and compared this data with data from the entire west coast (n = 369; 2006-2008). Modal classes from frequency distributions were 6 times higher in the latter (5 vs. 32 g/㎡). The mean and median values of the latter were 1.3 and 1.7 times higher (mean, 20.7 vs. 27.8 g/㎡; median, 17.1 vs. 29.5 g/㎡), and the maximum value was 3.4 times higher. Mood's median test showed significant difference at p-value = 0.01. We estimated the biomass-to-depth relationships from each data set by using Akaike Information Criterion and regarded the non-overlap of the 95% confidence intervals as indicating significant difference. The biomass was different from a 10 m depth below, and 3 times higher in the west coast at around 20 m compared with the maximum depth of the wind farm area. A local event of catastrophic sedimentation ranging from 1 to 2 m was observed in the wind farm during winter surveys. This could be a probable source of the lower biomass, but information on biomass seasonality and a natural experimental approach seem to be needed for the conduct of further studies. This study is meaningful in that it provided the background to assess future changes by understanding the lower level of benthic productivity in the area. We expect this study will contribute to the preparation of measures that can remove or mitigate the source of the lower biomass and improve the productivity of fishery resources in the area.

• 한국수산과학회지
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• 제30권5호
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• pp.759-770
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• 1997

제주해협내에 설정한 3개의 남북 단면상에 배열한 13개의 관측정점과 기타 4개의 제주항 부근의 연안정점에서 $1986\~1989$년까지 실시한 해류계에 의한 해류조사결과와 $1981\~1987$년 사이에 실시된 해류판 추적조사, 일반해양관측 등에 의하여 얻어진 자료들을 종합적으로 분석하여 정리한 제주해협의 유황을 요약하면 다음과 같다. 1. 제주해협내에는 주로 동$\~$북동류의 항류가 있어, 해협 서쪽 입구의 전단면을 통하여 해협내로 유입된 해수가 동쪽 입구의 전단면을 통하여 유출되고 있으며, 이 항류의 유속은 10m층에서 $5.2cm/sec\~30cm/sec$이고, 중${\cdot}$저층은 $1.3\~24cm/sec$로 대체로 해협의 심소 및 제주도 북측에 강류대가 있고, 추자도 및 보길도 부근의 연안 천소에 악한 항류가 있다. 2. 제주해협 서쪽 입구의 전단면에서 실측한 항류의 하계 평균유속은 6.93cm/sec로, 이것을 기초로 계산한 이 단면의 해수수송량은 $0.384\times10^6\;m^3/sec(Sv)$이며, 단면의 항류분포와 지형류 유속 분포간에는 많은 차를 보였다. 3. 추자도 북서쪽의 전선역에서는 밀물 때는 북향류에 의해 고온${\cdot}$고염분의 외해수가 5mile정도 연안역으로 이동 하지만, 썰물 때는 북상 거리만큼 다시 남하하지 않고 동$\~$남동향류 때문에, 연안수와 혼합하면서 전선북쪽의 연안역으로 이동하므로, 결과적으로 추자도 북서해역은 제주도 서방해역으로 부터 북상해온 외해수가 한국남해연안수내로 유입하는 창구가 되며, 이것을 일으키는 주된 작용은 항류가 아닌 조류이다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.896-898
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• 2012

최근 여러 나라들이 해양산업 개발에 관심을 가지면서 다양한 기술들이 개발되고 발전하고 있다. 이중 해양 환경에서 사용하는 무선 통신은 그 연구의 역사가 오래되었으며, 지금도 발전하고 있는 분야이다. 해양에서 무선을 이용한 환경 관측은 다양한 전파 매체를 통해 데이터 전송을 한다. 기술의 발달함에 따라 데이터 전송에서 문제점인 전원의 제한, 거리의 제한, 해수에 의한 부식, 수밀 등의 부분의 해양관측의 제약 요소 등에 관해서도 많은 발전을 거듭하였다. 이와 함께 점점 더 다양화되는 요구 데이터들과 실시간 관측 및 데이터 전송 면에서는 육상과 같이 다양한 통신방식과의 연계가 미흡한 실정이다. 이에 따라 본 논문에서는 연안환경, 어장 환경 등에서 활용 가능한 RF 통신을 이용한 Ad-Hoc Network를 구축하고 영상매체를 통한 실시간 관측과 센서를 이용한 환경 변화에 대한 데이터 수집을 통하여 효율적으로 관리할 수 있는 무선 관리 시스템을 구축하고자 한다.

• 수산경영론집
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• 제14권1호
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• pp.19-43
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• 1983

Mankind has made traditional use of various ocean resources in such several forms as fish, plants food, means of transportation, and military purpose, followed by the recent exploitation of offshore subsoil or sea-bed minerals, energies, and utilization of ocean space. These available ocean resources come from the marine natural environment which has a distinct feature in view of the relationship between human wants and their capacity to meet them. Though these socially basic resources however bring forth the so-called scarcity or differential rent, their communal nature of ownership dissipates free gifts of nature endowed to society as a whole. Thus to maximize these rents and social welfare thereof, rents should be secured and preserved through a well-defined arrangements of property-ownership as well as appropriate comparison of competing uses of marine resources, taking full cognizance of their irreversible adverse effects of a specific choice on the alternatives. Here I showed the sources of rent yielded from the multiple uses of navigation, fishery, mariculture, minerals, and recreation site, and also summarized the presently widely-known analytic tool to measure these rents with emphasis on due care of the telescopic faulty of the appraiser in charge, viewed from the communal point, Finally, as communal property is in strict sense owned by the public at large, notwithstanding the restricted communal ownership at government or local governments control, effectiveness of competition I expect should be kept while transferring claims of these resources from the legal owner to private enterprise as well as while extracting their rent by her. In particular, various national or social objectives look forward to tile maximization of social efficiency. Discretionary system in noncompetitive method thus, is exceptionally suggested because of probable suspicion from the public whether these resources are transferred as a give away or not in discretion. And these realized rent payments, I propose, should be wisely taken advantage of in advancement of scientific research in marine nature to bring an incremental rent therefrom successively.

• 수산해양기술연구
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• 제50권4호
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• pp.567-582
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• 2014

Coastal fisheries in Korean waters have highly complexity with a variety of fishing gears, and scale of those fisheries is smaller than that of offshore fisheries. As a result, important spawning and nursery grounds for many species of fish has been destroyed. The pragmatic ecosystem-based approach was developed for the assessment of fisheries resources in Korean waters by Zhang et al. (2009; 2010). As for the species risk index (SRI), common squid caught by coastal gillnet in the Uljin region had the highest risk. As for the fisheries risk index (FRI), coastal gillnet in the Uljin coastal waters had the highest risk. For the common squid which had the highest SRI, resources management strategies must be established such as catch prohibition of length and period with TAC. For the coastal gillnet in the Uljin region which had the highest FRI, it is judged to need management plans for conserving biodiversity as reducing the catch of non-target species and discards. Also to protect existing habitat, illegal fishery should be prohibited, and fishing gears should be designed in the environmental-friendly way considering when fishing gears lost.

• 한국수산과학회지
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• 제30권4호
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• pp.513-522
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• 1997

우리나라 주변 해역에서 어획되는 오징어 (Todarodes pacificus Steenstrup)의 주 대상 어업인 오징어채낚기어업의 어장 분포의 변화 및 수온전선대의 형성 양상과 어획량의 관계 등을 밝혔다. 한국 동해에서 오징어채낚기어업의 중심 어장은 4월에 북상하기 시작하여 8월부터 동해 중부에서 본격적인 어장이 형성되며, 울릉도 남쪽 해역에서 밀도 높은 어장이 형성되었다. 9월부터 남하하기 시작하나 어획량은 10월에 최고 값을 보였고 다음해 1월까지 어기가 지속된 후 2월부터 월동장으로 남하 회유하여 봄철에는 한어기를 맞이하였다. 동해의 주 조업 어장에서 형성되는 수온전선대의 형성양상과 오징어 어황과는 밀접한 관계가 있는 것으로 나타났다. 수온전선대가 주 조업 어장 내에서 동서 방향으로 형성되면 어군의 밀집이 이루어져 어황은 좋았고, 수온전선대가 연안을 따라 남북 방향으로 길게 형성되면 남한내 주 조업 어장에서는 어황이 좋지 않게 나타났다.

• 한국해양공학회지
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• 제26권1호
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• pp.78-83
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• 2012

The abundant nutrients contained in deep seawater are delivered by natural upwellings from the deep sea to the surface sea. However, the natural upwelling phenomenon is limited to specific areas of the sea; in other areas, the thermocline separates the surface sea from the lower layer. Thus, the surface layer is often deficient in nutritive salts, causing the deterioration of its primary productivity and ultimately leading to an imbalance in the marine ecosystem. Without a consistent supply of nitrogenous nutritive salts, they are absorbed by phytoplankton, resulting in a considerable problem in primary productivity. To solve this issue, a floating type of artificial upwelling system is suggested to artificially pump up, distribute, and diffuse deep seawater containing rich nutritive salts. The key technologies for developing such a floating artificial upwelling system are a floating offshore structure with a large diameter riser, self-supplying energy system, density current generating system, method for estimating the emission and absorption of CO2, and way to evaluate the primary production variation. Strengthening the primary production of the sea by supplying deep seawater to the sea surface will result in a sea environment with abundant fishery resources.

• 수산해양기술연구
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• 제51권4호
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• pp.553-560
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• 2015

The feeding habits of the Pacific bluefin tuna, Thunnus orientalis were examined based on the stomach contents of 330 specimens caught by offshore large purse seine fishery in the southern sea of Korea, 2011. The size of Pacific bluefin tuna used in this study ranged from 34.1 to 67.3 cm in fork length (FL). The percentage of empty stomachs was 41.8%. The main prey items were Pisces and Cephalopoda based on percentage IRI (index of relative importance). The main fish preys were Trachurus japonicus, Bregmaceros japonicus, Engraulis japonicus, and Cephalopoda were Todarodes pacificus, Loligo edulis, Watasenia scintillans. T. orientalis showed ontogenetic change in diet composition. Although Pisces dominated the diet of all length classes the portion of Cephalopoda was relatively higher in size between 40 and 50 cm other than length classes. In terms of seasonal variation in feeding habits, Pisces was the main prey group in all seasons, but Cephalopoda was also frequently consumed during spring and autumn based on %IRI.