• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.2
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• pp.2622-2633
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• 1972

This study was attempted in order to search for phyosical properties on various mix designs of concrete as ne of studies relating top revention against corrosion by action of sea water in the West Sea. In this study, as concerete mix design, fly ash, pozzolith and vinsolresin were used as admixtures for normal portland cement respectively, and pozzolan cement and normal cement were also used for each plain concrete. Concrete specimens were made and cured in accordance with the Korean Standard Specifications for concrete. In thetest, compressive strengths of the specimens were measured at the following ages; 7-day, 28-days and 3-months. Absorption test was made by immersing the specimens in water kept at boiling temperature for 5 hours. The results obtained from the tests are summarized as follows; 1. The use of fly ash as an admixture in mix design of concrete, has an effect on compressive strength at each age. But it is actually not effective on absorption by concrete, as the result of the fly ash concrete is almost the same at that of ordinary plain concrete. 2. The use of pozzolith as an admixture in mix design of concrete, has an effect on both of compressive strength at each age and absorption rate. The pozzolith is more effective than vinsol resin, relating to improvement for physical proreties of concrete. 3. The use of vinsol resin as an admixture in mix design of concrete, has also an effect on both of compressive strength at each age and absorption rate. As the above fact, effectiveness of the vinsol resin is some what lower than pozzolith, as far as physical properties of the concrete are concerned. 4. Plain concrete used pozzolan cement only is the most effective on both of strength at each age and absorption rate in this study. The pozzolan cement is characteristic of higher strenth as the age is later. 5. Relationship between compreessive strengths and absorption rates of the concrete is shown by a different regression line dependingon ages. The gradient of the regression line is steeper as the age is later. 6. Throught physical test, it may be expected that the use of pozzolith and vinsol resinas asan admixture respectively will be better resistant than fly ash or ordinary plain concrete and that plain pozzolan concrete will also be the best resistant to action of sea water due to improvement of theirphysical properties.

• Journal of Aquaculture
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• v.4 no.2
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• pp.73-84
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• 1991

Underground sea water is widely utilized for land based aquaculture in Cheju province, Korea nowadays. Salinity of this water($20{\~}30$ ppt) is slightly lower than natural sea water but because of its good water quality and temperature which is maintained at $16{\~}18^{\circ}C$ all year-round, many fish farmers are using this water for finfish culture. To evaluate the possibility of utilizing underground sea water for the seed production of the flounder, Paralichthys olivaeceus, hatching rate of fertilized eggs, survival rate of hatched larvae, and growth rate of the juveniles were tested with various salinity levels ranged from 14.1 ppt to 40.2 ppt. The salinity ranges which showed over $70{\%}$ survival rate for fertilized eggs to hatchout were 33.7 ppt${\~}$40.2 ppt, for hatched larvae to 2-day-old were 20.6 ppt${\~}$40.2 ppt, from 10-day-old to 12-day-old were 27.2 ppt${\~}$40.2 ppt, and from 45-day-old to 47-day-old were 20.6 ppt${\~}$40.2 ppt. Two hundred day old fingerlings showed no mortality when exposured to 7.6 ppt${\~}$40.2 ppt for 2 days. All fish died within 3 days when 45-day-old juveniles were transferred directly from normal sea water to 14.1 ppt sea water. However, they were all survived when transferred first to 20.6 ppt for 3 days then to 14.1 ppt sea water. The highest growth rates of fingerlings reared at 4 different salinities (33.7, 27.0, 31.0, or 15 ppt) were obtained at the 27 ppt group followed by 33.7, 21.0, 15 ppt respectively. The relationship between the days of rearing (X) and the total length of the fingerlings were as follows. $33.7\%$ group : Y=8.8109 + 0.1104X(r=0.999) $27.0{\%}$ group : Y=8.6797 + 0.1208X(r=0.997) $21.0{\%}$ group : Y=8.4081 + 0.1052X(r=0.990) $15.0{\%}$ group : Y=8.4309+ 0.0995X(r=0.990)

• Journal of Aquaculture
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• v.9 no.1
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• pp.43-55
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• 1996

The experiment was performed to evaluate the possibility of utilizing underground sea water for the seed production of tiger puffer, Takifugu rubripes. For this purpose, the effects of 6 different salinities (3.5, 7.0, 14.0, 20.0, 27.0, $33.0\%_{\circ}$) were determined based on the hatching rate of fertilized eggs, survival rate and the amount of food consumed by hatched larvae, where as the effects of 3 different salinities (20.0, 27.0, $33.0\%_{\circ}$) were also examined with rearing tiger puffer juvenile ($4.29{\pm}0.50$ cm in total length) for 50 days in the closed recirculating water system. As a results, either the hatching or the survival rate of more than $70.0\%$ were obtained from the fertilized eggs reared at the salinity of 27.0 to $33.0\%_{\circ}$, the early hatched larvae at 27.0 to $33.0\%_{\circ}$, and the 10-day-old larvae at 20 to $33.0\%_{\circ}$. At three different salinities, the survival rate of 20-day- and 30-day-old larvae turned out to be $89.0\%$ and $92.5\%$, respectively. The salinity for maximum food intake thus appeared to be from 27.0 to $33.0\%_{\circ}$. In this condition, 20-day-old hatched larvae consumed $323\~342$ Artemia nauplii and 30-day-old hatched larvae ate $1,559\~1,5791$ A. nauplii. The highest growth rate of fingerlings were observed at the salinity $27\%$ and followed by 33.0 and $20.0\%_{\circ}$, respectively. The relationship between the days of rearing (X) and the total length (Y) of the fingerlings were as follows : $33.0\%_{\circ}$ group : Y=0.107X-2.532 (r=0.982) $27.0\%_{\circ}$ group : Y=0.116X-3.195 (r=0.975) $20.0\%_{\circ}$ group : Y=0.116X-2.693 (r=0.987) The slopes of regression line estimated from $27.0\%_{\circ}$ and $33.0\%_{\circ}$ groups were significantly different from that of $20.0\%_{\circ}$ group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.639-643
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• 2002

Water quality, bacterial phase and fish growth rate were analyzed in the process of artificial seed production of flounder (Paralichtys oliraceus) larvae to investigate the water quality in rearing tank using Ultra Filtration System (UES). Sand Filtration System (SFS) and Ultra Filtration System (Ins) were set up in the experimental group. For the analysis of water quality, pH, salinity, DO, SS, COD, $NH_{4}^{+},\;NO_{2}^{-},\;NO^-,\;DIN$ (dissolved inorganic nitrogen) and DU (dissolved inorganic phosphate) were measured. There was no data difference between SFS group and UES group in most analysis items, but the UEs group showed low salinity and low 55 values, such that salinity was $33.5\%_{\circ}$ in SES group and $30.2\%_{\circ}$ in WS group and 55 was 15.5 mL/L in SES group and 7.0 mL/L for UPS group. For changes in bacterial phase and TBC (Total Bacterial Counts), in SES group, 6$\times$10^{5}CFU/mL in seawater decreased to the ratio of about 116, and TBC, Genus Vibrio and bacteria in the Genus Acinetobacter and Genus Micrococcus sharply increased after nine days, while stable bacterial phase was maintained low in UES group during the experiment except for Genus Ajteromonas. In the growth of the larvae, fish length was 17.0 mm (SGR 14.0) in the SES group and 18.8 mm (SGR 14.3) in the UFS group. It is concluded that when water is supplied for artificial seed production with WS, stabilization of water quality condition and inhibition of bacterial multiplication are possible. When production environment becomes stable, stable growth of fish becomes possible by reduction of environmental stress.

• Journal of Aquaculture
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• v.20 no.2
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• pp.96-105
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• 2007

A pair of maroon clownfishes with an indonesian native, reared in recirculation culture system to develope its aquaculture techniques. Courtship, spawning behavior, egg developments and rearing of the maroon clownfish larvae were documented. The larval development were described with illustrative figures. The spawning was occurred 8 times between Feburary and August 2004. The gravid female spawned during 15:00-20:00. The male mainly took care of the eggs supplying oxygen by water currents using their pectoral fins, anal fin and mouth. The fertilized eggs were separative-adhesive and oval in shape, and $1.99{\pm}0.03\;mm$ in longer diameter and $0.88{\pm}0.03\;mm$ in shorter diameter. The fertilized eggs were in deep-orange color. Cleavage occurred in 30 minutes after fertilization, and the egg reached 2 cells stage in 1 hour 10 minutes after fertilization at $27.0^{\circ}{\pm}0.5^{\circ}C$. The embryo was formed in 23 hours 40 minutes after fertilization. Hatching began in between $120{\pm}2$ hours and $150{\pm}12$ hours after fertilization at $27.0^{\circ}C$ in the incubator. Total length (TL) of the newly hatched larvae was 3.22 mm with mouth and anus opened. Ten days after hatching, mean TL of the larvae were 6.21 mm with 28 dorsal fin rays, 17 anal fin rays and 28 caudal fin rays. Nineteen days after hatching, mean TL of the larvae were 9.34 mm. At this stage the larva had three white bands on the body, and they began to feed on commercial diet.

• Journal of fish pathology
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• v.23 no.1
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• pp.69-83
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• 2010

This study was aimed to investigate the effects of injection of garlic, Allium sativum, extract and immersion in garlic juice on the nonspecific immunity and the resistance against the artificial infection of Streptococcus iniae and Edwardsiella tarda of the olive flounder, Paralichthys olivaceus. The nonspecific immune mechanisms were assessed in terms of lysozyme activity, nitroblue-tetrazolium (NBT) assay and superoxide dismutase (SOD) activity etc. Relative percent survival (RPS) was assessed by the challenge with S. iniae BS10 or E. tarda KE-1. Almost of the garlic extract injected groups showed the enhanced level of the tested nonspecific immune factors. In the challenge test with S. iniae and E. tarda, RPS of 5% garlic extract pre-injected group was much higher than that of any other tested groups, respectively. Almost of the garlic juice immersion tested groups exhibited strengthened nonspecific immune defence factors, lysozyme activity, the number of lymphocytes and neutrophils, NBT reduction and SOD activity in kidney. In the challenge with S. iniae and E. tarda, RPS in the 0.25 g/L of garlic juice immersed group was much higher than any other tested groups, respectively. The results suggest that the garlic extract and juice would be effective to enhance the nonspecific immunity and protective ability of olive flounder against fish disease such as S. iniae and E. tarda.

• Journal of fish pathology
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• v.23 no.2
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• pp.199-209
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• 2010

This study was aimed to investigate the effects in different immersion doses of garlic, Allium sativum, juice to modulate on the nonspecific immune responses of the olive flounder, Paralichthys olivaceus, artificially prechallenged with Streptococcus iniae BS10 and Edwardsiella tarda KE-1, respectively. The nonspecific immune responses of the tested fish were assessed in term of skin mucus lysozyme activity, the change of bacterial cell counts in organs, the number of lymphocytes and neutrophils in blood, and SOD activity. Almost groups of the prechallenged with either S. iniae BS10 or E. tarda KE-1 fish which had been immersed in garlic juice showed the enhanced skin mucus lysozyme activity, the number of lymphocytes and neutrophils in blood, and SOD activity in the kidney but the decreased the number of bacterial cell in surveyed organs. RPS in the group immersed in 0.25 g/L of garlic juice was much higher than in other immersed test groups. These results suggested that the garlic juice immersion can be effective on enhancement of the nonspecific immune responses and the protective ability of olive flounder to the artificial challenge with S. iniae BS10 and E. tarda KE-1.