• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.274-283
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• 2014

Swelling of the heat-treated netting for gillnet was estimated through the netting height in square acrylic tank. Experimental Nylon netting and PBSAT netting were heat-treated by using the high-degree vacuum method in hot water after net making. Heat-treatment temperatures were conducted with Nylon netting $105^{\circ}C$ and PBSAT netting $62^{\circ}C$, $65^{\circ}C$, $66^{\circ}C$, $67^{\circ}C$. The swelling measurement method of a netting using the square tank was capable of the reduction measurement errors comparing with measurement methods of a mesh inner angle and the shortening rate of a mesh size. In addition, this method was available to comparison evaluation for each netting more easily. Wet type heat-treatment apparatus with high-degree vacuum was shown higher $7{\sim}8^{\circ}C$ inner side temperature than a setting temperature. The tensile strength and elongation of Nylon netting and PBSAT netting were shown higher wet condition than dry condition. The tensile strengths of PBSAT monofilaments in dry and wet condition were sharply decreased at heat-treatment temp. $75^{\circ}C$ than heat-treatment temp. $74^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.637-641
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• 1999

This study was carried out to understand feeding ecology of black rockfish, Sebastes inermis in the coastal waters off Shinsudo, Sachon. The specimens were collected by angling, gill net, small danish seine, and long-bag net from February 1984 to May 1985. The fish consisted of 5 age groups from 0 to 4. Feeding activity was more intensive in the early morning and late afternoon in spring and summer, but the fish showed intermittent feeding activities in autumn and winter. Although the food items of the fish changed slightly by seasons and with growth of the fish, main food items were cope pods, gammarids, caprellids, carideans, polychaetes, and brachyurans. Of these food items, cope pods were major preys for the fish of age group 0, and gammarids over age group 1. Evenness and diversity of the food items increased as the fish grew. In consideration of feeding organs, digestive organs and stomach contents of the fish, S. inermis seemed to be not only carnivore but also visual feeder consuming mainly small crustaceans.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.3
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• pp.221-229
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• 1990

The horizontal distribution of squid gill-net fishing ground in the North Pacific Ocean was examined within the main fishing season, May to October, during 1986~1989. Data of sea surface temperature were selected from Technical Reports of National Fisheries Research Development Agency of Korea, Data Records of Hokkaido University, Deep-sea Training Reports of Korea Fishing Training centre, Fishing Operation Reports of Daelim Fisheries Co., Ltd., Oyang Fisheries Co., Ltd. and Dong-won Industrial Co., Ltd.. Data of catch were also collected from Deep-sea Training Reports of Korea Fishing Training Centre and Fishing Operation Report of three fisheries companies in Korea. The fishing ground was segmented in every 1 degree of latitude from $34^{\circ}N$ to $46^{\circ}N$ and 2 degree of longitude from $144^{\circ}E$ to $162^{\circ}W.$ The distribution and centeroid of fishing ground, fished and optimum surface temperature, catch per unit effort (CPUE) in the fishing ground were computed, based on the above data. The resulted obtained can be summarized as follows: 1. Range of fishing ground can be estimated as $35^{\circ}~40^{\circ}N,$ $178^{\circ}~166^{\circ}W$ in May, $36^{\circ}~41^{\circ}N,$ $178^{\circ}E~166^{\circ}W$ in June, $38^{\circ}~44^{\circ}N,$ $170^{\circ}E~170^{\circ}W$ in July, $39^{\circ}~44^{\circ}N,$ $144^{\circ}~180^{\circ}E$ in August, $39^{\circ}~44^{\circ}N,$ $144^{\circ}~170^{\circ}E$ in September and $40^{\circ}~44^{\circ}N,$ $144^{\circ}~154^{\circ}E$ in October. 2. Fishing ground in May, June and October is similarly distributed along longitude and latitude, but the range of the former is larger than that of the latter in July, August and September. Monthly centeroids of fishing sectors is estimated as #3888 in May, #3884 in June, #4078 in July, #4154 in August, #4146 in September and #4044 in October respectively. 3. Fished temperature and optimum and temperature are estimated as $14.0~18.5^{\circ}C$ and $15.0~16.0^{\circ}C$ in May, $13.5~18.5^{\circ}C$ and $14.5~16.0^{\circ}C$ in June, $14.0~20.0^{\circ}C$ and $14.5^{\circ}C,$ $19.0^{\circ}C$ in July, $16.0~21.5^{\circ}C$ and $18.0~20.0^{\circ}C$ in August, $14.5~22.0^{\circ}C$ and $17.0~18.5^{\circ}C$ in September, $14.0~18.0^{\circ}C$ and $16.0~17.0^{\circ}C$ in October. 4. Monthly mean CPUE which corresponds to the net weight of catch(kg) divided by the sheet number of operated gillnets is calcuted as 3.2, 4.5, 4.3, 5.1, 6.4 and 5.8 kg/sheet respectively. 5. Considering the monitoring program of the squid gill-net fishery in the North Pacific Ocean during 1989~1990, set by the Korean Government, 12 sectors may be restricted out of 21 fishing sectors in May, 7 out of 24 in June, 4 out of 25 in July. They are free from restriction hereafter August.

• Journal of fish pathology
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• v.12 no.2
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• pp.101-105
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• 1999

In a survey of net-caged yellowtail Seriola quinqueradiata in the southern parts of Korean Peninsula, we found infestations of ciliate in the gills of the moribund fish during the abnormally elevated temperature. The ciliate was very similar to genus Colpoda Muller, 1773 on morphological and reproductive characteristics. Histopathological changes revealed that the ciliate invaded gills only, causing extensive destruction of the gill filaments including lamella without any clinical signs found in the other organs and tissues. This is the first record of the parasitic ciliate in cultured yellowtail.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.237-242
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• 2002

최근 우리나라 연안어업은 한일, 한중어업협정, WTO 가입 등으로 주변 환경이 급격하게 변화되는 한편, 연근해 어자원의 감소와 근해어업과의 경쟁조업 등으로 인해 경영수지가 극도로 악화되고 있다. 이로 인해 연안어민들의 최소 생계기반 마저 위협받고 있는 실정이다. 이에 본 연구는 연안어업의 수익향상과 자원관리 측면에서 경제성 연안 어선의 선형개발 방안을 검토하였다. 이를 위해 새로운 어선어업 환경에서 요구하는 자원관리, 채산성보장 등의 경제 사회적 요건을 기술적 요소로 변환하여 다목적어선의 개념을 설정하고 관련 기초자료를 마련하였다. 특히, 연안어업을 동해, 서해, 남해, 서남해 등으로 나누어 허가업종의 실태와 어민 요구사항이 서로 다른 점을 감안하여 다목적화 가능 업종을 선정하고, 선형개발 방안을 도출, 정리하였다.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1315-1323
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• 2013

The purpose of this research is to evaluate the effects of a commercial mixed extruded pellet(EP) and raw fish moist pellet(MP) diet on diseases prevalence and serological constituents and HSI of korean rockfish, Sebastes schlegeli grown in two commercial-scale aquaculture farms from June to December in 2009. The growth of MP-fed rockfish was slightly faster than EP-fed rockfish during experimental period, but did not show significant differences. The levels of TCHO, TG, Glucose and TP in the MP-fed rockfish group were higher than those of EP-fed group, whereas there was no significant difference in other biochemical factors of blood between two groups. In addition, bacteria and virus were not detected in both MP- and EP-fed rockfish groups, and the infection rates of gill fluke between two groups did not show clear difference. In conclusion, there was no comparable difference in growth and the health extents of one year rockfish by administration of the commercial mixed extruded pellet(EP) and raw fish moist pellet(MP) diets.

• Korean Journal of Ichthyology
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• v.23 no.4
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• pp.310-313
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• 2011

This is the first report of Aprion virescens, belonging to the family Lutjanidae, collected in Korea. The specimen (151.4 mm in standard length) was caught by the gill net in the coastal waters of Jeju Island on 30 October, 2009. This species is characterized by having a deep vertical groove in front of eye, very short pectoral fin almost equal to snout length, and four black spots on dorsal fin. We propose a new Korean name, "Nok-saek-tung-dom-sok" and "Nok-saek-tung-dom" for the genus and species, respectively.

• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.71-75
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• 2007

Acute toxicity of BDR-29, a combined preparation of Cassia Semen, Prunellae Spica, Tribuli Fructus, and Uncariae Rhamulus et Uncus was examined using male and female Sprague-Dawley rats. Rats were treated with the BDR-29 intra-gastrically at 0 mg/kg, 5 mg/kg, 50 mg/kg, 500 mg/kg or 2,000 mg/kg and observed for two weeks. At the doses used no mortality or abnormal clinical signs in animals were shown during at the observation period. Also there was no difference in net body weight gain, gross pathological findings, and urine analysis at the terminal sacrifice among the groups rats treated with different doses of the test substance. The results suggested that acute oral toxicity of BDR-29 in rats is very low at the conditions employed in this study.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.1
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• pp.30-38
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• 2014

Hydro-acoustic survey was carried out to investigate the spatial characteristics of fish distribution near two artificial reefs (AO: large octagonal semi-sphere and AC: combined custom built) having different types in Jeju marine ranching area. The survey system consisted of scientific echo sounder (EK60), DGPS system, and ECDIS (Mecys). Field survey was conducted on August and October 2012 with star survey and line transect survey line method, and species composition was investigated from gill net fishing survey. The acoustic signals from individual fishes and small fish schools were mainly recorded around AO, but large and strong signals from large fish school were mainly detected in the top layer of and the water column near AC. The echogram suggest that the fish aggregation for the two types of AO and AC exist the significant difference in fish species and spatial distribution pattern.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.404-409
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• 2016

We investigated the maturation and spawning of Sebastes thompsoni in the coastal waters off Ulleungdo, based on samples collected by gill net from March 2013 to February 2014. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length (TL) at 50% group maturity. The average TLs of female and male S. thompsoni were 22.6 cm and 22.5 cm, respectively. The main parturition period of females was during March and April. The GSI of females began to increase in January, and reached a maximum in March. The GSI of male reached a maximum between January and February. The spawning period of males was shorter than that of females. The egg diameter during gestation stage was 1.4±2.1 mm. The TL of females at 50% group maturity was 22.3 cm.