• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.125-125
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• 2003

Recirculating aquaculture systems consist of different treatment compartments that maintain water quality within the ranges of commonly recommended for fish culture. This paper presents the common considerations in designing different treatment compartments as well as the engineering criteria in designing closed recirculating aquaculture system including a circular tank for fish culture, a sedimentation basin and a foam fractionator for solids removal, two styrofoam bead filters for TAN removal, a sand filter for nitrate removal, and aerators. The main purpose is to outline a common procedure in designing of closed recirculating aquaculture system for marine fish culture.

• Journal of Aquaculture
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• v.7 no.1
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• pp.9-20
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• 1994

To find out suitable indoor rearing tank shape and stocking density of the abalone Haliotis discus hannai, young abalones were reared in the square or ellipse shape tanks with various stocking densities and were fed dried sea mustard, Undaria Pinnatifida HARVEY for three years. There were no significant differences between the square rearing tank and the ellipse one in growth rate and survival rate. With regard to vertical design of rearing tanks with three floors, the significant differences were not found among culture floors. However, the growth and survival rates of young abalones from the running water system were significantly higher than those of the abalones from the circulating system (P< 0.05). For the stocking density experiment with 1,000, 1,500 and 2,000 individuals of 20 mm young abalone, there was no significant differences in growth and survival rates among these groups. However, in that of 200-400 individuals of 40 mm abalone and 100-300 individuals of 50 mm abalone, the lower stocking density of young abalone showed the higher growth and survival rates. The lower stocking density and the smaller size of young abalones showed the higher daily feeding rate and feed efficiency.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.673-677
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• 2006

A perfusion culture of transgenic Nicotiana tabacum cell suspensions, transformed to express recombinant glucuronidase (GUS), was successfully performed in a 5-1 stirred tank bioreactor. With 0.1 $day^{-1}$ of perfusion rate, the maximum dry cell weight (DCW) reached to 29.5 g/l in 16 days, which was 2.1-fold higher than the obtained in batch culture (14.3 g/l). In terms of the production of GUS, the volumetric activity could be increased up to 12.8 U/ml by using perfusion, compared with 4.9 U/ml in batch culture. The specific GUS activities in both perfusion and batch cultures were maintained at similar levels, 200-400 U/g DCW. Consequently, a perfusion culture could be a good strategy for the enhanced production of recombinant proteins in a plant cell culture system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.457-468
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• 1995

In order to develop a more practical culture system from the present running seawater tank system, two experiments of environmental factors, growth, survival rate and rearing density of olive flounder (Paralichthys olivaceus) were carried out for two consecutive years. Two groups of fish in initially averaging 7.5cm of total length, and 3.4g of body weight (EXP. I) and 5.0cm and 1.8g (EXP. II) were reared in the semi-closed recirculating seawater system equipped with the rotating biological contactors with the commercial culture scale. The dissolved inorganic nitrogen concentrations is EXP. I ranged 0,247-0.512 ppm of $NH_4-N$ (0.010-0.043 ppm of$NO_2-N$, and 0.108-0.342 ppm of $NO_3-N$, and those in EXP. II were 0.091-0.715 ppm, 0.002-0.045 ppm, and 0.007-0.277 ppm, respectively. Daily feeding rates of the fish were $0.67-2.41\%$ in EXP. I and $0.69-2.22\%$ in EXP_ II, and teed efficiency were $34.8-59.8\%\;and\;40.5-88.4\%$ in EXP. I and II, respectively. The average total ten說h and body weight were 40.0-42.8cm and 695.0-852.69g after 340 days culture in EXP. I, and 36.7-39.7cm and 552.4-706.4 g after 365 days culture in EXP. II, respectively. Survival rates of the fish at the end of EXP. I and II were $92.0\%\;and\;96.0\%,$ respectively. The ratio to body surface area of non-ocular side in all fish to bottom area of rearing tank, so-called covering rate, was used as an indicator of rearing density. The highest cowering rate and weight density of fish per $m^2$ of rearing tank at the end of experimental period were 2.2 and 34.1kg in EXP. I, and 2.6 and 36.3kg in EXP. II, respectively. For the commercial culture of olive flounder, the semi-closed recirculating seawater system was found to be more effective than the running seawater tank system in aspect to the fish productivity and protection of marine environment.

• Journal of Environmental Science International
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• v.23 no.1
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• pp.129-142
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• 2014

To treat chromaticity contained in effluents of dyeing wastewater efficiently, potent dye-degrading microorganisms were isolated from influent water, aeration- tank sludge, recycle water and settling-tank sludge located in leather and dyeing treatment plant. Six potent strains were finally isolated and identified as Comamonas testosteroni, Methylobacteriaceae bacterium, Stenotrophomonas sp., Kluyveromyces fragilis, Ascomycetes sp. and Basidiomycetes sp. When Basidiomycetes sp. was inoculated into ME medium containing basal mixed-dyes, 93% of color was removed after 8 days incubation. In the same experiment, the 1:1 mixed culture of Basidiomycetes sp. and photosynthetic bacterium exhibited 88% of color removal; however, it showed better color removal for single-color dyes. The aeration-tank and settling-tank samples revealed higher color removal (95-96%) for black dyes. The settling-tank sample also revealed higher color removal on basal mixed-dyes, which resulted in 90% color removal after 6-h incubation. From the above results, it is expected to achieve a higher color removal using the mixed microorganisms that were isolated from aeration-tank and settling-tank samples.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.89-95
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• 1997

The current processer of the textile wastewater treatment are mostly consisted of a combination of a physico-chemical and a biological treatment. The overall efficiency of these processes is, however, assessed to be fairly low. It is even worse during the summer season when temperature of the wastewater rises above 40$\circ $C. Therefore, a feasible process of the textile wastewater treatment which can work efficiently at higher temperatures was investigated in this work. We used a bench scale reactor consisted of one 4 liter anaerobic and one 8 liter aerobic tank, and the thermophilic symbiotic PVA degraders, Pasteruella hemolytica KMG1 and Pseudomonas sp. KMG6 that had been isolated in our laboratory. In the preliminary flask experiments, we observed that the thermophilic symbiotic PVA degraders could not grow in the wastewater substrate. Then, we isolated the mutant strains by acclimating the KMG1and KMG6 strains to the wastewater medium. The mutant symbionts (KMG1-1 and KMG6-1) were isolated through 6 times successive transfers into the fresh wastewater medium after 5 days culture for each. The mutant strains obtained grew well in the mixed medium composed of 75% wastewater and 25% synthetic medium, and supplemented with 0.5% PVA as a sole carbon source. During the culture for 14 days at pH 7.0 and 40$\CIRC $C, the bacteria assimilated about 89% of the added PVA. The symbionts degraded equally well all the PVA substrates of different molecular weight (nd=500~30000). In contrast to the flask experiments, in the reactor system the mutant strains showed very low levels of the PVA and COD removal rates. However, the new reactor system with an additional aerobic tank attained 82% removal rate of COD, 94% of PVA degradation and 71% of color index under the conditions of 5% inoculm on the tank 2, incubation temperature of 40$\circ $C, dissolved oxygen level of 2~3 mg/l and retention time of 30 hours. This result ensures that the process described above could be an efficient and feasible treatment for the PVA contained textile wastewater at higher temperatures.

• Journal of Intelligence and Information Systems
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• v.10 no.3
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• pp.39-57
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• 2004

Many dairy producers periodically receive information about their bulk tank milk with reference to bulk tank somatic cell counts, standard plate counts, and preliminary incubation counts. This information, when collected over a period of time, in combination with bulk tank mastitis culture reports can become a significant knowledge base. Several guidelines have been proposed to interpret farm bulk tank milk bacterial counts. However many of the suggested interpretive criteria lack validation, and provide little insight to the interrelationship between different groups of bacteria found in bulk tank milk. Also the linguistic terms describing bulk tank milk quality or herd management status are rather vague or fuzzy such as excellent, good or unsatisfactory. The objective of this paper was to develop a set of fuzzy descriptors to evaluate bulk tank milk quality and herd's milking practice based on bulk tank milk microbiology test results. Thus, fuzzy logic based reasoning methodologies were developed based on fuzzy inference engine. Input parameters were bulk tank somatic cell counts, standard plate counts, preliminary incubation counts, laboratory pasteurization counts, non agalactiae-Streptococci and Streptococci like organisms, and Staphylococcus aureus. Based on the input data, bulk tank milk quality was classified as excellent, good, milk cooling problem, cleaning problem, environmental mastitis, or mixed with mastitis and cleaning problems. The results from fuzzy reasoning would provide a reference regarding a good management practice for milk producers, dairy health consultants, and veterinarians.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.563-570
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• 1985

The main purpose of this study is to evaluate a revolving plate-type biofilter system for mass culture of eels (Anguilla japonica) based on the experimental rearing for 199 days. Water quality, growth efficiency of fish and effects of fish disease control were critically evaluated. The experiment was conducted in two different units, each unit consisting of a cement tank containing $20m^3$ of water. In unit A, a biofilter which includes 400 rotating undulated P. V. C. plates being 70 cm in diameter which rotates at 6 rpm and also 400 undulated P. V. C. plates fixed in the settling chamber of an area of $66{\times}62cm$. Water was continuously passed through the filter at a rate of 260 l/min., and supplemental water was added to the fish tank at a rate of $4m^3$ a day. In unit B, the biofilter has 400 P. V. C. plates being $66{\times}62cm$ each was installed in the settling tank. The results gained from the experimental rearing for 199 days from April 21, 1984 to November 5, 1984 are as follows. In the growth experiment, the weight of fish in unit A increased from 3.0 kg to 815.6 kg, while in unit B, from 3.0kg to 416.0kg. During the period of the experiment, in the both units the fish grew at an acceptable rate at the temperature at which they were held. Observing every aspect of eel culture, including growth rate, disease control and water quality, unit A appears to have adventages over unit B, which makes it particuraly attractive in intensive recirculating fish culture system. It was further observed that certain parasites such as Trichodina sp. and Costia sp. could easily be controled by appling 4 ppm of $KMNO_4$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.103-110
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• 1983

The main purpose of the present study is to evaluate a revolving plate type biofilter system for mass culture of eel(Anguilla japonica) based on the experimental rearing for 120 days (Oct. 1982-Feb. 1983). Water quality changes, growth efficiency of fish and fish disease treatment were critically evaluated. A revolving plate type biofilter system was designed(Fig. 1). The system consisted of a glass tank (150 l), a revolving plate biofilter and a settling tank(150 l). The biofilter consisted of 60 submerged quadriangular plates ($28{\times}37$ cm) and 30 revolving plates (32 cm diameter) for a total of 19.0 $m^2$ of surface area. The revolving plates were made to rotate 10 time per minute, The total water volume of the rearing system were 300 l, and everyday 1/3 of the total water volume were changed with freshly prepared water. In the rearing system a total of 2 kg of eel (1,500 individuals, mean weight:1.3 g) were reared fed on the pellet feed and the dough feed. The growth efficiency were much better for the pellet feed (FC: 1.79) compared to the dough feed (FC: 3.56). During the experimental rearing water quality control was satisfactory. Total ammonia concentrations were 0.38-0.59 ppm and nitrite concentration were 0.83-1.19 ppm. On the other hand alkalinity decreased from 176ppm just after the water change to 17ppm just before the water change. The low alkaline condition was compensated by the regular change of water. Epidemics of parasitic gill-flocks (Pseudodactvlogylus sp.) was observed, and they were easily eliminated by the treatment of DDVP (1.0 ppm). Trichodina sp. and Costia sp. were observed, and they were also controlled by the treatment of potassium permanganate (4.0 ppm).

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.153-160
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• 2009

A phytoplankton cultivation system was installed and operated for removal of nutrients from stream water polluted by nonpoint source pollution. The system was a continuous-flow culture comprising a phytoplankton tank that received inflow from a storage reservoir. When the system was operated as a batch culture for the purpose of determining hydraulic retention time (HRT), the proper HRT value was three days, and the removal rate of TP and TN averaged 70% and 44%, respectively. When the system was operated with the continuous flow from a stream for 45 days, 53.9% of TP and 53.1% of TN were removed as sludge. Due to active growth of phytoplankton, pH and dissolved oxygen in the phytoplankton tank were extremely high, reaching 10.8 and 16mg $L^{-1}$, respectively. It was concluded that nutrients can be effectively removed from polluted stream waters by cultivating phytoplankton.