• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.23-28
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• 2007

The residue depletion of streptomycin was investigated in the olive flounder (Paralichthys olivaceus), rockfish (Sebastes schlegeli), and red sea bream (Pagrus major) after consecutive three days treatment with dipping water at a dose of 20 g/ton water. Fishes were sampled for muscle on 1st, 2nd, 3rd, 4th, and 5th day after treatment. Streptomycin concentrations were determined by high performance liquid chromatography with tandem mass spectrometry. The recovery rates of streptomycin in muscle samples ranged from 87.2 to 102.3% and from 80.4 to 94.1% for the concentration of 0.05 mg/kg and 0.1 mg/kg, respectively. Streptomycin concentrations detected on the 1st day after treatment were 0.066, 0.058, and 0.073 mg/kg in muscles of olive flounder, rockfish, and red sea bream, respectively. At day 2, residue concentrations of all samples were believed to decrease to lower than 0.05 mg/kg, the detection limit. From results of the present study, a withdrawal period of streptomycin is proposed on 3 days after consecutive three days treatment with dipping administration at a dose of 20 g/ton water to avoid the presence of excessive residues of the edible muscles of olive flounder, rockfish, and red sea bream. The present study showed that residue concentrations of streptomycin decreased to below 0.05 mg/kg after treatment 2nd day.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.697-704
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• 2001

In this study, we investigated that the survival and growth responses of freshwater cladoceran Moina macrocopa and estuarine cladoceran Diaphanosoma celebensis on the saline culture conditions after transferring for using as live food organism. Estuarine cladoceran D. celebensis was survived and grew on the all salines except to saline jump culture condition of 0 ppt. However, freshwater cladoceran M. mcrocopa was died or decline on the over saline jumping culture conditions of 4 ppt within 5 minutes. These suggest the possibility of using the estuarine cladoceran D. celebensis compare with freshwater cladoceran M. macrocopa as a substitute live food organism for Artemia in the marine larval rearing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.56-62
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• 1986

Marine fishes, sardine(Sardinops melanosticta), scad kingfish(Caranx equula), horse mackerel(Trachurus japonicus) and file fish(Navodon modestus), were stored for fifty days with partial freezing at$-3.5^{\circ}C$. During the storage, the changes in microflora and volatile nitrogen content was investigated. The fishes exhibited $10^4\;to\;10^6$ of bacterial cells per square centimeter of their skin just before they were submitted to the storage. The bacterial cell number was increased as $10^6\;to\;10^8$ cells as the storage time passed over twenty-two days. Offensive odor which is typical in the spoilage of fishes became strong as increase the bacterial cell numbe. The major isolates among the three hundred strains of bacteria isolated from the fish skins were identified as Pseudomonas I/II, III/IV-H, Vibrio and Moraxella. The same was found in the spoiled fishes, however, Pseudomonas I/II, was predominant on contrast to that of fresh fishes. Pseudomonas III/IV-NH, Flavobacterium, Cytophaga and Micrococcus were also found in early period of storage, but they disappeared as the progress of storage. Nine per cent of isolates were unidentified.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.244-249
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• 2006

The residue depletion of amoxicillin was investigated in the olive flounder (Paralichthys olivaceus), rockfish (Sebastes schlegeli), and red sea bream (Pagrus major) after 7 days treatment with medicated feed at a dose of 400 mg/kg bw/day. Fishes were sampled for muscle on 1st, 2nd, 3rd, 4th, and 5th day after treatment. Amoxicillin concentrations were determined by high performance liquid chromatography with fluorescence detector. The recovery rates of amoxicillin in muscle samples ranged 84.3-101.3% and 75.0-91.5% for the concentration of 0.05 mg/kg and 0.1 mg/kg, respectively. Amoxicillin concentrations detected on 1st day after treatment were 0.137, 0.131, and 0.172 mg/kg in the muscle of olive flounder, rockfish, and red sea bream, respectively. After a withdrawal of 3 days, muscle concentrations were 0.012, 0.010, and 0.017 mg/kg in the olive flounder, rockfish, and red sea bream, respectively. Amoxicillin was not detectable in muscle samples on 4 days following withdrawal of the medicated feed. From results of the present study, a withdrawal period of amoxicillin is proposed on 4 days after 7 days treatment with medicated feed at a dose of 400 mg/kg bw/day to avoid the presence of excessive residues of the edible muscles of olive flounder, rockfish, and red sea bream.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.8
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• pp.1097-1103
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• 2012

There are many fish farms being cultivated in the southwestern cost of South Korea. Because the farms cultivating use the basic method that inflow and circulate sea-water, slight negligence and bad design cause major negative impact on fish deaths. Also, the optimal temperature for each specie of fishes has already been proven to differ on each specie. Maintaining this environment, regardless of seasons, is very difficult and that requires research to develop. In this paper, basic characteristics of heat and mechanism of heat transfer are studied. Based on this, Open-end water vessel is designed and constructed using sandwich-insulation panels and simulated to store the heat in certain isolated space. This study confirmed that it is possible to keep constant temperature by this method, in large areas of water where it is insulated by heat insulator. and equipped with heater in Open-end water vessel where the other part is heated. The AC power controller maintains the constant temperature required and the temperature controller detects and displays the temperature by using the micro-processor.

• Journal of Navigation and Port Research
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• v.37 no.5
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• pp.487-492
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• 2013

Underwater acoustic communication has multipath error because of reflection by sea-level and sea-bottom. The multipath of underwater channel causes signal distortion and error floor. In order to improve the performance, it is necessary to employ an iterative coding scheme. Among the iterative coding scheme, turbo codes, LDPC codes and convolutional code based on BCJR algorithm are dominant channel coding schemes in recent. Therefore this paper analyzed the performance of iterative codes based on turbo equalizer with the same coding rate and similar codeword length. The performances of three kinds of iterative codes were evaluated in the environment of underwater acoustic communication channel that are real data collected in Korean east sea. The distance of transmitter and receiver was 5Km and data rate was 1Kbps. As a result, convolutional code based on BCJR algorithm has better performance in underwater channel than turbo codes and LDPC codes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.908-913
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• 1998

The productivity of land based seawater fish farm has been decreased because of unexpected outbreaks of diseases caused by the contaminated inlet seawater. Sometimes unfiltered/untreated outlet seawater from the land based seawater fish farm has created serious environmental problem. In the needs of treatment systems for the inlet and outlet seawater, the researchers have developed two different systems, The purpose of this study is to design and test two treatment systems, the screen filter for inlet seawater and drum filter for outlet seawater, on the basis of concept of system design and automatization. After developing two systems, an experiment has been conducted with two systems and collected data to improve design and efficiency of the system. In this study, detailed design and efficiency of the system could be improved by the programmable logic controller (PLC).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.1
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• pp.12-16
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• 1988

The observation of the tidal current and the bottom contour around the set net fishing ground were carried out at four different regions of the southern part of Korea in order to obtain the basic information on the migrating course of fishes. The bottom contour was surveyed with portable echo sounder, and the tidal current was observed by two different methods at the same time. One was 25 hour observation at the fixed position with self-recording current meter (Inter Ocean Model 135 type) and the other was the drift observation of radar reflectors. Most of the set nets have been set near bottom valleys. It was regarded that the fish school became to dense easily near the valley according to the combined effect of the tidal current and the bottom contour.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03a
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• pp.289-309
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• 2004

위에서 언급한 바와 같이 계측대상 연약 지반이 대심도, 광역화함에 따라 연약지반 계측의 전반적인 추세는 자동계측 시스템의 사용과 준설ㆍ매립공사 또는 해수면상에서의 공사 특성상 케이블 관리의 어려움을 극복하고자 무선데이터 전송방식의 사용이다. 또한 유지관리의 필요성 증대로 인하여 계측 모니터링, 자동분석 프로그램의 기술도 발전되고 있다. 그러나 아직 국내는 계측에 대한 기술 개발이 미비할 뿐 아니라 계측기술에 대한 인식이 매우 부족하고, 관련법이 정비되지 못하여 계측관련 기술 및 경험이 전무한 영세업체들까지 난립하여 치열한 경쟁을 하는 관계로 기술개발에 대한 투자는 거의 중단된 상태이다. 따라서 정확한 유지관리 계측을 위해서는 대부분 외산기기에 의존할 수밖에 없는 상황이다. 그러나, 현재 국내의 전자통신 기술의 수준을 감안할 때 관련법이 정비되고 체계적인 연구와 투자가 이루어진다면 쉽게 세계적인 수준으로 도약할 수 있으리라 판단된다. 한국지반공학회의 연약지반위원회에서는 2003년 8월 20일 한양대학교 박물관 강당에서 학술세미나를 개최하였다. 본격적인 세미나에 앞서 '연약지반 공학자의 당면문제 및 해결방안'에 관한 주제로 전 연약지반위원회 위원장이셨던 (주)에스코 컨설턴트의 김승렬박사께서 초청강연을 하여 주셨다. 김승렬박사께서는 그 원고의 꼬리말을 다음과 같이 기술하며 마무리하셨다. 국내 연약지반 기술수준의 상황과 우리의 위상을 제고하기 위한 좋은 말씀으로 생각되어 본고에서는 그 부분을 인용하는 것으로 끝을 맺고자 한다. '우리나라의 연약지반 기술수준은 동남아시아 지역의 국가들인 싱가포르, 대만, 태국, 심지어는 베트남에 비해 결코 우월한 위치에 있지 않다. 오히려 많이 낙후되었다고 할 수 있다. 경제규모와 위상과 발전상태에 비추어 보면 실로 부끄러운 일이 아닐 수 없다. 이렇게 된 배경에는 연약지반이 사회의 문제로 대두되는 일이 미미하여 이 분야에 쓸리는 관심이 상대적으로 적은 점이 주원인이라고 볼 수 있다. 연약지반이 기술현장에서 문제로 떠오르기 시작한지도 째 오랜 시간이 경과하였다. 이제 더 이상 우리의 기술수준을 이대로 방치할 수는 없는 시점에 와 있는 것이다. 연약지반에 몸담고 있는 우리 스스로가 위상을 지키려는 노력을 배가하여야 한다. 연약지반 공학자들은 스스로 고급의 데이터를 생산하고 평가하고 예측하는 기법을 활발하게 적용하고 발전시킴으로써 자신들의 위치를 지켜야 할 것이다. Clean-handed-research만을 고집하는 환상에서 깨어나 국외의 변모하는 모습을 빠르게 수용하고 국내의 연약지반 관련 자료를 국외에 널리 알릴 수 있는 위치로 발돋움할 때 연약지반 공학자의 위상도 제고될 것이다.'

• Journal of fish pathology
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• v.25 no.3
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• pp.173-180
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• 2012

Vibriosis is one of the most prevalent fish disease belonging to the genus Vibrio. In present study, Vibrio sp. isolated from Japanese eel was confirmed as Vibrio scophthalmi using analysis of the genomic sequence of 16S rRNA. The major signs were hemorrhage of body surface and inner surface of abdomen, severe enteritis and retention of ascitis. Histopathological examination revealed blood cell degenerations in various organs (gills, liver, spleen, kidney, heart, intestine), exfoliate of intestinal epithelium, and congestion and hemorrhage in intestinal lamina propria. This is the first case report on V. scophthalmi infection in Japanese eel Anguilla japonica.