• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.3
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• pp.183-190
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• 1993

A cooperative Korea-Japan investigation for the demersal fisheries resources of the East China Sea carried out by using the training ship Oshoro Maru belong to Hok-kaido University, Japan, during 1-8 November, 1991. The research vessel sampled 15 stations with demersal trawls on the East China Sea, and 1,364 nautical miles of track line were surveyed hydroacoustically. The hydroacoustic observations were taken with a scientific echo sounder operating at two frequencies of 25 kHz and 100 kHz, and a microcomputer-based echo integrator. Fish samples were collected by demersal trawling, and temperature, salinity and dissolved oxygen were measured with a CTD system. The target strength of fish school was estimated from the relationship between mean scattering strength and catches caught by demersal trawling. The results obtained can be summarized as follows: 1. The mean backscattering strength for 15 layers occupied by demersal trawls at 25 kHz ranged from -70.4 dB to -59.1 dB. Then the catch per one hour ranged from 8.2 to 587.5 kg/hour. 2. The mean backscattering strength for the entire layer between transducer and seabed in the survey area of the East China Sea at 25 kHz and 100 kHz were -68.0 dB and -73.1 dB, respectively. 3. The mean fish-school target strength per one kilogram at 25 kHz and 100 kHz were -28.3 dB/kg, and -30.4 dB/kg, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.124-130
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• 2014

We aimed to assess the behavior characteristics of fish on an artificial reef using hydroacoustic techniques. The acoustical survey was conducted with a 200 kHz dual beam transducer while fishing on the stone combination reef of Uljin. A school of fish were detected on the artificial reef before sunset and floated on the artificial reef at 30 minutes after sunset. The density (Nautical Area Scattering Coefficient, NASC) of fish that floated on the artificial reef after sunset was about $600m^2/nmi^2$; similar observations (about $50m^2/nmi^2$ or less) were noted after 19:00 hours. Fish caught by fishing on the artificial reef were Sebastes schlegeli, Hexagrammos otakii, Sebastes thompsoni, and Conger myriaster. Resultantly, we demonstrated that hydroacoustic techniques are useful for detecting behavior characteristics of fish in the artificial reef. Such results can be used for basic data to estimate the install effect of the artificial reefs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.162-166
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• 2011

The distribution and occurrence of Charybdis japonica larvae were investigated off Yeonpyong-do, Korea, in the Yellow Sea. C. japonica larvae were collected monthly at 15 stations from early June to late October in 2006 and 2007. At each station, a Bongo net with 303 and $505{\mu}m$ mesh was deployed once with a double oblique tow. No larvae were caught in June, in both years. Zoea I was predominant in late July in 2006 and early August in 2007, whereas Zoea I accounted for 84% of all larvae collected and no larval stages later than Zoea III were sampled. Megalopa were the most abundant larval stage at all stations in late August in both years. The timing of larval hatching of C. japonica may be related to that of phytoplankton blooms in the study area. The finding that Zoea I and Megalopa were predominant in the study are may indicate that C. charybdis larvae are carried by advection.

• Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.12.1-12.15
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• 2018

A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year.

• The Journal of the Korean dental association
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• v.15 no.2
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• pp.115-120
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• 1977

Extensive avulsion of the scalp, or stripping of a large area of soft tissue from the skull, is a serious accidnet. The avulsed scalp is often injured otherwise, such as by crushing, tearing, or from multiple laceration. The surrounding skin may be devitalized. Replacement of the scalp is usually followed by necrosis and sloughing within a short time. In such instances, the outer table of the cranium may become sucessively exposed. dry, dead, and affected by osteomyelitis. Hence the securing of early healing to prevent these is of the utmost importance. The successful case of reimplantation of the completely avulsed scalp, which is exposured to air for about 14 hours, is reported, in which there was partial growth of hair afterwards. The avulsed scalp caused by her long hair being caught in a grain belt was contaminated with hairs & dust. Authors treated this 19-year old female patient by split thickness skin graft, intermediate skin graft, full thickness skin graft from her own avulsed scalp.

• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.375-378
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• 1993

The prevalence of Intestinal parasite Infections In Inhabitants at the reaches of the Hantan River, Chorwon-gun, Korea, was observed from August 12 to September 14, 1993. Of 465 people observed by cellophane thick smear and formalin-ether concentration method, 2 Ascots lumbricoides (unfertilized), 1 Trichwis Dichturn, 39 Clonorchis sinensis and 16 Metagonimus egg positive cases were found. After treatment, the Metogonimus egg positive cases passed out flukes of Metogonimus Mlyata type. Of 68 fish caught In the Hantan River, 14 (20.6%) were Infected with metacercanae of Metogontmn, while no metacercana of C. sinenis was found. At this area, soul-transmitted nematodes are very low, but clonorchlasis and metagonlmlasis are prevalent by modernate endemicity.

• Journal of fish pathology
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• v.25 no.3
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• pp.243-247
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• 2012

Histopathological observations on a epidermal papilloma of wild red halibut (Hippogossoides dubius) caught at the area around Echung Island and Gogunsan Islands were done. The papilloma formed on the dorsal fin was the same color with the body on the ocular side but black on the non-ocular side. Under light microscopy, the tumor on the skin was very similar to epithelial papilloma supported by connective tissue. X-cell-like cells in the tumors were large and eosinophilic with a centrally-located, large nucleus. But the characteristic large nucleolus in the nucleus of the x-like cells was indistinct clear in this specimen because about 6-9 hours have passed after catching the fish and autolysis have occurred.

• Journal of fish pathology
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• v.22 no.2
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• pp.163-166
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• 2009

The ectoparasite ciliate Trichodina has been recorded from above 100 species of freshwater and marine fishes. In April 2009, we investigated the trichodia infection in 13 species of marine fishes captured by emplacement net and gill net in order to understand trichodina infection status among the natural fish populations along the Namhae-Gun coast area, the southen coast of Korea. Trichodina infection was observed in 10 out of 10 sea basses Lateolabrax japonicus, 2 out of 5 finespotted flounder Pleuronichthys cornutus and 1 out of a stone flounder Kareius bicoloratus. The sea bass infected with the parasite showed hypertrophy and exfoliation in gill epithelium. In addition, hyperplasia and lamellar fusion of gill filament were noticed among naturally affected sea bass.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.3
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• pp.288-297
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• 2019

This study conducted a survey using a sampling inspection method and acoustic technique for continuous monitoring of useful organisms and non-commercial fish species distributed in the water of Gwangyang Bay, and evaluated the marine resources. In June, 2018, 38 species were caught in the shrimp beam trawl, comprising 3,594 marine organisms with a total weight was 65,415.3g. The acoustic survey showed that the nautical area scattering coefficient (NASC; $m^2/n.mile^2$) for the waters of Gwangyang Bay was highest in Transect 15 ($1,655.5m^2/n.mile^2$) and lowest in Transect 1 ($1.3m^2/n.mile^2$). The biomass was estimated to be 2,634.9 tons in the acoustic survey. This indicates that the acoustic survey method detected more fish shoals than the sampling inspection method.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.25-33
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• 2021

Species composition and variation of catches in the coastal waters of Sinsan of Jeju Island were determined using samples collected by a set net from May 2014 to October 2015. During the survey period, a total of 55 species (51 species, 35 families and 11 orders in fishes, 4 species, 2 families and 2 orders in cephalopods) were occurred, and Perciformes (28 species) were dominant fishes in this area. In the number of individuals and biomass, the small pelagic fishes such as Trachurus japonicus and Scomber japonicus were occurred abundantly, and both species accounted for 95.9% of the total catch by a fishing logbook of a set net. In the results of length-frequency distribution of small pelagic fishes caught by a set net in Sinsan, T. japonicus showed a range from 3.5-19.1 cm (average 8.8 cm) and S. japonicus showed a range from 7.0-25.6 cm (average 16.8 cm). In addition, these were mostly immature fishes.