• 한국지구과학회지
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• 제26권2호
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• pp.129-136
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• 2005

Continued observation of ARGO floats for years(about 4 years) makes the conductivity sensor more vulnerable to fouling by marine life and associated drift in salinity measurements. In this paper, we address this issue by making use of floats deployed in different years. Floats deployed in the East Sea and the Indian Ocean are examined to find out float-to-float match-ups in such a way that an older float pops up simultaneously with a newer deployment (with tolerable space-time difference). A time difference of less than five days and space difference of less than 100km are considered for the match-up data sets. For analysis of the salinity drift under the stable water mass, observations of the floats from deepest water masses have been used. From the cross-check of ARGO floats in the East Sea and the Indian Ocean, it is found that there is a systematic drift in the older float compared to later deployments. All drift results, consistently show negative bias indicating the typical nature of drift from fouled sensors. However, the drift is much less than 0.01, the specified accuracy of ARGO program.

• Journal of Plant Biology
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• 제8권4호
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• pp.7-25
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• 1965

In order to clearify the microflora of the lower course of the Han River and the effect of the marine water on the Han River, the study was carried out at Paldang, Kwangjang, Noryangjin, and Haengju for 4 months (from May till September in 1965). The results obtained are as follows: 1) Water temperature, transparency, light intensity, pH, silicate, and salinity were determined as environmental conditions. 2) Samples collected from 4 stations were identified and classified by Engler's classification system. It resulted in 4 Phyla, 3 Classes, 13 Orders, 25 Families, 61 Genera, 155 Species, and 16 Varieties. The total numbers of phytoplanktons identified are 171. Of the number, 106 species and 12 varieties were recorded in this paper for the first time. 3) A comparative observation on the distribution of marine phytoplanktons and salinity in the Han River showed a fact that the Han River was biologically affected in the middle portion between Noryangjin and Haengju by marine water. Furthermore, the salinity determined at Haengjuduring a day(at high tide, September 26, 1995) supported the above fact. 4) Four species among the identified species are saprobic planktons and it is regarded as the forms derived from Chunggyechon.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.206-211
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• 2002

The aim of this study was to obtain the basic data on the fish school behavior change to approaching vessel and fish species identification by means of their swimming speed. The surveys were carried out for the juvenile southern blue fin tuna and other fish schools off Esperance, western Australia from January to March 1999. We observed changes of fish school behavior in response to the approaching vessel using 360-degree scanning sonar. The results showed that, a horizontal direction index used to quantify a change of fish school behavior did not identify dependence of a radial distance and a swimming speed. A Mann­Whitney test conducted using the horizontal swimming speed of both species identified by sonar specialists, did not reveal a significant difference.

• 한국환경과학회지
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• 제18권1호
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• pp.15-19
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• 2009

Early studies claimed that heterotrophic dinoflagellates Pfiesteria piscicida and related genera may produce a putative water-soluble toxin that causes death of fish and other marine animals. Several methods were tested to visualize plate morphology of Cryptoperidiniopsis brodyi and Pfiesteria piscicida. Cellulose plates of cells were exposed and visualized- by a membrane stripping method using Triton X-100. While calcofluor M2R white stain could readily bind to the thecal plates, details of the plate tabulation were difficult to observe. Fixation with osmium tetroxide $(OsO_4)$ produced well preserved cells with little morphological distortion, but thecal plates could not be visualized. Scanning electron microscopy (SEM) observation using the membrane stripping method showed distinctive plate tabulations between C. brodyi and P. piscicida suggesting that this method is a useful tool for morphological identification of lightly armored dinoflagellates.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2004년도 수산관련학회 공동학술대회 발표요지집
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• pp.512-512
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• 2004

Venus clam, Protothaca jedoensis was collected in lune 2003 from Yosu, Korea. The prevalence and infection intensity of Perkinsus was determined by Ray's Fluid thioglycollate medium technique and Choi's 2 M NaOH digestive assay. The prevalence of infection was 80% in Yosu; 54.2% in Taejon and 15.5% in Sachon. Consequently, infection intensity was highest in clams from Yosu (6250${\pm}$8188 Perkinsus cells/g of tissue) whereas lower levels were found in Taejon (5072${\pm}$10862 Perkinsus cells/g of tissue) and in Sachon (2452${\pm}$15300 Perhnsus cells/g of tissue). Histological observation showed that Perkinsus presented in mantle, gills, digestive tubes and gonad of clams. The hemocytic infiltrations and tissue damages were found in heavy Perkinsus-infected clams. Results after immunofluorescence staining with antibody developed from Perkinsus atlanticus suggested that there is closed relationship between Perkinsus found in Venus clam and Manila clam.

• 수산해양기술연구
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• 제47권2호
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• pp.146-152
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• 2011

Underwater CCTV camera systems are increasingly replaced the traditional net approach of assessing the species, numbers and aggregation patterns of marine animals distributing around the artificial reefs installed in the inshore fishing grounds, in particular, in relation to the biological investigation of behavior and distribution patterns of target fishes. In relation to these needs, we developed a multi-directional underwater CCTV camera system to use in detecting and tracking marine animals in the artificial reef ground. The marine targets to be investigated were independently tracked by using a camera module toward the bottom and four camera modules installed in the interval of $90^{\circ}$ in horizontal plane and inclination of $45^{\circ}$ in vertical plane of the CCTV system without the overlap of video frames by each camera module. From the results of several field tests at sea, we believe that the developed multi-directional underwater CCTV camera system will contribute to a better understanding in evaluating the effect of artificial reefs installed in the inshore fishing grounds.

• 한국소음진동공학회논문집
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• 제26권6_spc호
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• pp.705-713
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• 2016

Underwater noise produced by ships has been becoming an increasing issue. A dominantly contributing noise source is a ship propeller. Therefore, it is important to predict the propeller noise at the propeller design stages. This study applied the acoustic analogy based on Ffowcs Williams equation for the prediction of the marine propeller BPF noise. A marine propeller BPF noise is investigated experimentally as well as numerically. Propeller BPF noise measurement and propeller cavitation observation tests are performed in the KRISO medium size cavitation tunnel. Numerical prediction schemes of marine propeller BPF noise are presented together with the noise measurement method. Propeller BPF noise predictions and experiments are performed under the various propeller operating conditions including non-cavitating and caveating conditions. Numerical and experimental results are compared and analyzed. It is shown that numerical prediction results are generally in good agreement with the measured data.

• 한국항해항만학회지
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• 제32권10호
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• pp.751-757
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• 2008

본 논문에서는 월별 해양사고건수를 이용하여 국내 해역의 해양사고에 관한 통계적인 기초분석을 수행하였다. 이를 위해서 해역간 해양사고건수의 차이여부, 연간 해양사고건수의 차이여부, 그리고 월간 해양사고건수의 차이여부 등을 국내 해역별 및 어선과 비어선으로 나누어 일원분산분석을 통해 확인하였다. 그리고 추가적으로 사후분석을 수행하여 분석그룹에 대한 평균차이의 검정을 하였다 결론적으로 해역간 사고건수에는 서해, 남해, 그리고 동해순으로 많았고 서로 유의한 차이가 있었다. 연간 사고건수의 차이에서는 어선의 경우 남해와 동해에서, 비어선의 경우 남해에서 유의한 차이가 나타났다. 또한 월간 해양사고건수에 대한 차이에서는 어선에 대해서만 서해와 동해에서 서로 유의한 차이를 보였다.

• 한국해양학회지:바다
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• 제4권2호
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• pp.155-159
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• 1999

수중음향을 이용한 풍속 측정(Weather Observation Through Ambient Noise: WOTAN) 기술을 이용하여 소형 기상관측부이를 개발하였다. 소형기상관측부이는 지상자료 수선소와 기상부이 간의 통신수단으로 휴대전화망을 채택하였다. 제작된 소형기상관측부이를 부산시 기장군 시랑리 부근 해역에 계류하여 부근에 위치한 국립수산진흥원에 설치한 지상기상관측기기에서 관측된 결과와 비교하였다. 수중음향을 이용하여 추정된 풍속을 지상에서 관측한 풍속과 비교한 결과 좋은 결과를 얻었다. 즉 풍속계에 의한 풍속과 수중음향에 의해 추정된 풍속의 rms 오차가 1 m/s 내외로 나타났다. 이 소형기상관측부이의 한가지 단점은 휴대전화의 통달거리가 짧아 육지에서 멀리 떨어진 곳에는 설치가 불가능하다는 점인데, 현재 전 세계 대양에서 통화가 가능한 위성 휴대전화망이 상용화되기 시작하여 위성 휴대전화를 이용하면 이 문제는 쉽게 해결될 수 있다고 본다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2008년도 공동학술대회
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• pp.73-78
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• 2008

지각구조 연구 및 연안 속도구조 등의 조사를 위해 한국해양연구원에서 제작된 광각 탄성파 탐사기록 장비인 해저면지진계 및 소노부이 시스템의 특징을 살펴보았으며, 실해역 시험 탐사를 통해 그 유용성을 살펴보았다. 해저면 지진계 및 소노부이 시스템은 정상적으로 작동하였으며, 전형적인 광각 탄성파기록을 얻을 수 있었다. 특히 소노부이 기록상에서 기반암 등 지하구조에 의한 초기 굴절파의 이벤트가 나타났으며, 이는 굴절법 탐사 혹은 토모그래피 등을 통해 지하속도 구조 탐사가 가능함을 보여준다.