• The Journal of the Acoustical Society of Korea
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• v.25 no.3E
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• pp.101-109
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• 2006

Besides dorsal-aspect target strength (TS) of the fish, side-aspect TS information is also acoustically important parameter in fisheries acoustics. In this study, the side-aspect TS of 11 black sea bream (Acanthopagurus schlegeli) were measured using a split beam echosounder of 120, 200, and 420 kHz; total length of the fish ranged from 12.4 to 23.7 cm, and wet weight from 27.5 to 229.8g. For the precise TS measurement with side-aspect angle, we used anesthetized and tethered specimens of known size while being rotated through $360^{\circ}C$ by means of a carousel structure. The side-aspect TS measurements of the fish were conducted by rotating the fish in the horizontal plane at 50 interval. The ping interval was 0.2 second and elapsed time at each angle was 30-60 second. As a result, the measured side-aspect TS data were fitted by sinusoidal function. The relationships between fish length and near full side-aspect TS were as follows: $TS_{120kHz}= 21.46 log (TL)-67.5 (r = 0.70), \;TS_{200 kHz}= 31.03 log (TL)-76.9 (r=0.83),\;TS_{420 kHz}= 30.79 log (TL)-72.2 (r = 0.77)$. For comparison, theoretically estimated side-aspect TS from the Kirchhoff ray mode (KRM) model, which based on swimbladder and body morphology, were compared with the measured TS.

• Proceedings of KOSOMES biannual meeting
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• 2005.11a
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• pp.139-141
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• 2005

It is important to manage artificial fish reefs with installation for restoration. we made survey for installation's condition(location, amount etc), fish community and amount of fishing net around installation area(6,142ha) in Yeosu of artificial fish reefs with side scan sonar and diving. Also we suggests better method of management after installation of artificial fish reefs.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.65-75
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• 2020

This study is a convergence study of 596 high school girls in order to confirm the relationship between the desired number of meat side dishes and preference of fish side dishes in school meals. Data were analyzed by χ²-test, ANOVA-test, and Duncan's test using SPSS 22.0 program. The results of the study were as follows. The scores of the subjects for promoting palatability were highest in the items 'Easy to eat' and 'Without fishy'. The scores of 'Nutrition Education', 'Combined with Preferred Food', 'Without Fishy' and 'Add Preferred Flavor' tended to increase significantly as the desired frequency of meat side dishes increased from 'less than three times a month' to 'more than five times a week'. The findings of the study confirmed the relationship between the desired frequency of meat side dishes and preference of fish side dishes. Therefore, this study is expected to provide high school girls with a way to increase fish preference.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.273-281
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• 2013

The movement patterns of fish aggregations swimming freely near artificial reefs on August 24, 2006, at Suyeong Man, Busan, Korea, were acoustically investigated and analyzed. Acoustic surveys were conducted using a 70kHz split-beam echo sounder, 330 kHz side-scan sonar and a 310 kHz imaging sonar. Algorithms for tracking the movement of fish aggregations swimming in response to artificial reefs were developed. The travel direction and the swimming speed for two aggregations of fish were estimated from the trajectory orientations of echo responses recorded by the imaging sonar.The first group was floating just above the reef structure, while remaining in the midwater column, and the second group was swimming through and around artificial reefs near the seabed. The mean swimming speed was estimated to be 0.40 m/s for the midwater fish aggregation and 0.17 m/s for the bottom aggregation close to artificial reefs. These results suggest that the swimming behavior of fish aggregations passing close to artificial reefs near the seabed displayed a slower moving pattern than fish floating just above the reef structure in the midwater column.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.588-596
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• 2014

To examine the influences of water temperature and stocking density on feeding, growth and blind-side hypermelanosis of the starry flounder Platichthys stellatus, we performed an experiment with fry at two densities: 2 and 8 fish/L. The fry had a total length of $3.2{\pm}0.1cm$, body weight $0.6{\pm}0.1g$, and pigmented patches (pigmented ratio $2.6{\pm}0.4%$) on the blind side. Duplicate experiments were conducted in 93.7 L glass tanks for 120 days, from July to November. We determined daily food intake (DFI), food efficiency (FE), growth, survival rate, ratio of hypermelanic fish, and pigmented area rate on the blind side at 60-day intervals. The DFI was less than 50 mg/fish/day, and growth was delayed from July to September (water temperature [WT]> $20^{\circ}C$). After October, when WT < $20^{\circ}C$, the DFI increased significantly and the growth was accelerated, suggesting that the rearing temperature of starry flounder in artificial facilities should be < $20^{\circ}C$. While the FE, and survival did no differ between the two density groups, DFI and growth were significantly higher at 2 fish/L than at 8 fish/L. There was no difference in the pigmented area ratio between the two density groups. Although the hypermelanosis was not correlated with body size, the malpigmentation increased with growth. These results suggest that a high stocking density is not the main cause of blind-side hypermelanosis, although it can accelerate hypermelanosis in the starry flounder.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.624-627
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• 2009

Design of ocean fishways as eco-movement passages for turbine structures, sluice structures and barrages of a environmentally-friendly tidal power system through which fish can pass are suggested. The ocean fishways comprise a plurality of fishways to allow fish to move between the sea-side and the lake-side of the barrages and turbine structures and sluice structures. It is demonstrated that the inventive ocean fishways are cost effective to construct and environmentally-friendly eco-movement passages for fish and benthos to move between sea-side and lake-side without passing through the turbine blades of a tidal power plant in operation.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.160-161
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• 2005

It is important to manage artificial fish reefs with installation for restoration. The instruments of survey for artificial reefs condition(location, amount etc.) is Side Scan Sonar and Multi-beam sonar. The efficient and economic survey of the artificial reefs facility is the complete survey of the SSS(Side Scan Sonar) in all area first and then the survey of the artificial reefs by MBES(Multi Beam Echo Sounder) in the finding area.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.1098-1106
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• 2016

To study the influence of light intensity on blind-side hypermelanosis of starry flounder, Platichthys stellatus, we compared growth, glucose, cortisol, ratio of malpigmented blind-side area, ambicolored fish ratio and expression of mch mRNA for 60 days in 0 lux(darkness) and 20 lux(low light density). The test was done in duplicate at 50 fish/tank with the selected ordinary juvenile flounder. The rearing was performed in FRP aquarium tanks ($H100cm{\times}L100cm{\times}W100cm$). Growth was higher in the 0 lux. The ratio of malpigmented blind-side area and ambicolored fish ratio were significantly higher at the 0 lux than at the 20 lux. The result suggests that 20 lux could inhibit the hypermelanosis. The expression level of MCH 1, 2 mRNA was significantly lower in 0 lux, indicating that MCH 1, 2 and light intensity are related to blind-side hypermelanosis of starry flounder.

• Journal of the Korean Society of Food Culture
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• v.14 no.2
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• pp.67-81
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• 1999

The present study was surveyed for the normal meal and particular folk meal in east cot area in Kyungpook province, Pohang, Youngduk, and Uljin areas. The results are as below: Most subjects for surveying were 30-40 years old and permanent residents in those areas. For the normal meal, the boiled rice was the top main dishes among 18 main dishes. The folloing upper five main dishes were boiled bean rice, boiled barley rice, boiled miscellaneous cereals rice, noodles, and Bbimbab (miced rice with cooked various vegetables and meats). Less frequent main dishes were raw fish Bbimbab and the various fish soups etc. The two upper side dishes, out of 17 surveyed ones, were kimchi and soybean paste soup. Twelve dishes(about 70%) out of 17 side dishes, the loach soup, the marinated and fermented raw fishes (fish Sikhae'), the baked mackerel, the pickled fishes, the friedsardine, the green seaweed, and the quid, etc. were made from the sea products. For the particular folk meal, about 30 kinds of the specific folk food items of this area were surveyed: Gudungchi' Sikhae', which was made with seaweed, out of the 11 kinds of fish Sikhae', raw fish(Whae') in water, Sigumjang', a salty agar, a steamed seaweed which was covered with the flour or bean power the various kinds of fish soups, the various kinds of fish stews were the particular folk side dishes in these areas. The dietary habit in these east coast areas were affected by the various sea food products, the fishes and the seaweeds, which were acquired easily through four season in these area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.266-272
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• 2013

The objective of this study was to monitor and evaluate the schooling characteristics, including the distribution density (volume backscattering strength) and acoustic size (target strength), of commercially valuable species swimming in response to artificial reefs installed at Suyeong Man, Busan, Korea. Fish aggregations at two artificial reef areas and at a nearby natural rocky reef habitat were recorded and analyzed using a 70 kHz split-beam echo sounder and 330 kHz side-scan sonar from August to September, 2006. An underwater CCTV camera system was also used to observe marine organisms in physical contact with and swimming very close to artificial reefs. During the acoustic observations at three reef sites, useful information about schooling characteristics of fish aggregations responding to artificial reefs were obtained, but more trials are needed to confirm significant differences in schooling behavior and geographical distributions in areas containing natural reef structures and artificial reefs.