• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2023년도 춘계학술대회
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• pp.204-205
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• 2023

본 연구는 준지도학습(SSL)을 기반한 소형 어선의 충돌 경보 송출 예측 모델에 관한 연구이다. 지도학습(SL) 방법은 레이블링된 다수의 데이터가 필요하지만 레이블링 과정에서 많은 자원과 시간이 소요된다. 본 연구는 '지능형 해상교통정보 서비스'와 연계한 데이터 파이프 라인을 통해 수집된 서비스 데이터와 실해역 시험에서 수집한 데이터를 사용하였다. 실제 사용자 만족도 기반으로 레이블이 결정된 실해역 시험 데이터만 아니라 레이블이 결정되지 않은 서비스 데이터를 함께 학습시킨 결과, 모델 정확도가 향상되었다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2021년도 추계학술대회
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• pp.139-141
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• 2021

중국 어선의 국내 NLL 침범하여 이루어지는 불법 조업이 최근 가을 성어기에 특히 늘어나고 있다. 불법 조업 어선의 단속 또한 해경에서 단속정으로 수행하지만 난폭성으로 쉽지않은 현실이다. 우리 관할 해역에서 단속 수위를 높여도 불법 조업어선이 지능화 및 난폭화 되어지고 있으며, 치어와 산란기 어종 등 금어기에도 조업하여 어민의 불만이 심각해지고 있다. 또한 불법조업 현장은 연평도 뿐만 아니라 서해, 동해 등 여러 지역으로 확산되고 있어 국가 차원에서 대응책마련이 필요하다. 대응책을 위하여, 이러한 불법조업시 법적 제제를 위한 증거를 제시하기 위하여 침범한 중국 어선의 항해장비로 식별된 조업 위치, 항적에 대한 증거와 통계 데이터가 필요하다. 이에 본 연구에서는 이러한 증거 수집을 위하여 단속한 중국 어선이 탑재하고 있는 항해장비의 종류를 분석하고자 한다. 특히 중국 어선이 탑재하는 장비는 자국내에 판매되는 항해장비의 종류와 제조회사 그리고 장비의 모델에 대하여 우선 파악하며, 특정 업체 장비에 대한 항해장비에 대한 포렌식을 처리하는 사례적인 모델을 제시하고자 한다. 또한 중국 어선이 탑재한 항해 장비에 대한 포렌식을 위한 국내 단속 시스템 측면에서 어떠한 정보가 수집 되어야 하고 분석되어야 하는지를 검토하고자 한다.

• Journal of Advanced Marine Engineering and Technology
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• 제33권1호
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• pp.166-174
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• 2009

Gijang Sea is located on the southeastern coast of Korea. This study establishes a basic system to identify optimal sites for the wave power generation. To achieve this goal, the field measurements were made at the field site in front of Dong-am fishing port at Gijang. In addition, we analyzed the offshore wave data at the Donghae buoy operated by Korea Meteorological Administration(KMA) and compared the data with the wave characteristics in Gijang Sea. The main results were as follows. In winter, the wave direction in Gijang Sea ranged between east and south($90{\sim}180^{\circ}$). The main wave direction was east($90^{\circ}$). The Significant wave heights and periods were under 2 m and $5{\sim}15$ sec, respectively. A comparison of water depth and wave direction constitutes one(condition) of the important parameters for selecting the optimal site for the wave power generation.

• 수산해양기술연구
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• 제40권2호
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• pp.144-148
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• 2004

해저에 설치된 파이프에서 분출되는 기포에 의해 형성된 강한 수평압력분포를 이용하여 선박을 신속 하고 정밀하게 유도, 정박시키는 도선시스템으로 항구, 협수로, 해협 등과 같이 복잡한 수상, 수중 장애물 지역에서 선박을 신속하고 정밀하게 유도함과 동시에 협소한 부두에 안전하게 선박을 정박시키기 위하여 본 도선 시스템을 고안하였다.

• 한국항해학회지
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• 제1권1호
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• pp.17-26
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• 1977

A large number of the set-nets are set in Namhaedo coast of Korea. The floats of these set-nets are not only small even in case of large floats but also they scarcely have distinguishable marks such as light buoys or flags, so that they are very hard to be recognized by naked eyes and thus became probable obstacles to navigation for the passing ships and the fishing vessels. In order to research the capability of detecting such nets with Radar, the author investigated a maximum detectable range of the ordinarly large floatsand of a floating corner reflectors of various size and shape by Radar. The results obtained are as follows; 1. A maximum detectable range of large floats at a close range can be calculated by the Radar equation in sufficient accuracy. 2. Large floats of the large set-nets are also detectable by Radar even though it's detectable range boundary was within 0.2-0.65 miles. And the Radar picture of large floats was easier to be found with somewhat higher setting of the gain control on shorter range scale of the 1 mile. 3. Floating corner reflector rather suitable for set-net floats of "S" type reflector proposed in this paper, of which the dimension must be above 17cm in diameter to be detectable by Radar at 2 miles.t 2 miles.

• 수산해양기술연구
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• 제49권4호
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• pp.341-351
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• 2013

Physical characteristics of PA (Polyamide) gill net and biodegradable gill net made by PBS (Polybutylene succinate) (mesh size 63mm, mesh thickness number 2, 2.5, 3) were analyzed to investigate catching efficiency of the biodegradable gill net for Pacific herring. Total 11 numbers of catching efficiency tests were carried out using commercial fishing vessel at Imwon port in Kangwon province from May to June 2013. The amount of catches were 1,535.7kg (18 species) through the catching efficiency tests and it is expected that the practicalization of biodegradable gillnet is possible because there is no difference for catches between PA gillnet and PBS gillnet. Catches of herring according to the thickness of net twine was the highest at No.2 and the thicker net twine tends to decrease the catches.

• 해양환경안전학회지
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• 제5권2호
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• pp.1-14
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• 1999

To find characteristics and areas of greater risk of oil spill at the coastal waters in Korea, some of risk factors were analyzed with historical data of oil spill and marine traffic. As a result, it is characterized that frequency of oil spill is increasing year by year and greatest percentage of spill source is fishing boat. It is proposed that the ports of Ulsan, Yeosu, Incheon and Pusan will be designated as primary area of risk as they have a higher risk of oil spills and its response authority is required to maintain appropriate regional response capability for prompt and effective response to a future spill incident. In addition, the regional response equipments at Ulsan are examined under a assumption of a medium size spill and it is found that the use of chemical dispersant can be an alternative when mechanical containment and recovery is not feasible in this area, and the existing response equipments may be appropriate to address that size of spill. However, the response authority is required to maintain more numbers of stronger boom for unsheltered waters and more quantity of concentrate dispersant to disperse all spilled oils on the water, furthermore the response authority should be prepared for a possible future catastrophic spill with sufficient equipments.

• 한국항해학회지
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• 제22권3호
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• pp.9-16
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• 1998

Loran C is a low frequently , pulsed. hyperbolic radio aid to navigation system, which operates in the 90 to 110 kHz frequency band. The position accuracy is not excellent but the repeatable and relative accuracy is very good, and it is very useful for fishing vessel in coastal waters. The operation of China north sea chain9GRI 7430) was begun on January, 1996, and in order to evaluate the accuracy of this chain, it was observed with Loran C receiver (LC-90, Furuno) in July 9 and December 30, 1997 at the fixed position of Kunsan national university. The obtained results were as follows : The time difference error of M-X, M-Y pair were $0.5{\mu}s$, $4.4{ \mu}s$ respectively and the mean time difference of M-X, M-Y pair were $15120.4{,\mu}s$ $32085.4{\mu}s$ respectively. The Loran C signals were received steadily and the daily fluctuation of time difference was very small. The longitudinal position error was very much than latitudinal position error, and the mean position error was about 1091.8m.

• Animal Systematics, Evolution and Diversity
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• 제33권1호
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• pp.8-16
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• 2017

We firstly described a box jellyfish, Carybdea brevipedalia collected from the southern coasts of Korea. It is morphologically characterized by gastric phacellae, a special digestive system of cubozoan jellyfish, and velarium, the thin muscle flap forming the opening of the subumbrellar cavity. The phacellae are linear-shaped, comprising numerous cirri branched from multiple roots. Each root also has multiple numbers of cirrus bundles. Basis of velarial cannels parts into two branches in each octant of velarium. Its geographic distributions were limited to Jeju-do and the middle-southern coasts where the organisms are seriously hazardous to bathers in summer. Numerous individuals and/or large-sized populations were observed specifically from beaches at Jeju-do, Namhae-do and a small fishing port of Namildae, while only a small amount of the individuals was observed in Gamak Bay, Jaran-Goseung Bay, and Geoje-do. We confirmed molecular identity of the Korean C. brevipedalia with comparison of nuclear ribosomal DNA sequences. Until now, Carybdea brevipedalia is the only cubozoan species reported to be distributed in Korean waters.

• 소음진동
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• 제6권4호
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• pp.503-511
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• 1996

There is a tendency of using the resilient mounting system to control the structure born noise transimitted from a engine of which weight is comparatively light and of which speed is comparatively high. According to recent reports, the resilient mounting system is applied to control the vibration of a engine running up to 300 - 400 R.P.M.. Furthermore, the resilient system is also used to the ships such as marine exploring ships, fishing boats, and military vessels. It is not desirous to apply the results for the resilient mounting systems of automobile engines to the controls of the vibrations of marine engines. Marine engines are worked under the idle speed in port and are operated up to the maximum contineous revolution at sea(running up condition). And marine engines are usually worked in inevitable conditions such as a misfire and a cut-off cylinder operating condition. Concerning the above running conditions, a resilient mounting system should be designed in the case of marine engines. In this paper, we studied the effect of engine's misfire on the resilient mounting systems. And the influences of design parameters, such as dynamic characteristics and fitting angles of resilient rubber mountings, were also investigated respectively on the single and double resilient mounting systems.