• Fisheries and Aquatic Sciences
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• 제7권2호
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• pp.76-83
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• 2004

To supply fresh and quality quarantined seafood in live seafood specialty restaurants, facilities for short-term culture or holding of live marine fish and shellfish are a necessity. In this study, the performance of a simple recirculating aquarium system for the culture and holding of marine fish was evaluated. The aquarium system consisted of a culture tank, a foam fractionator for solids removal, and a Styrofoam bead filter for nitrification and solids trapping. In the first trial, the aquarium was stocked with a total of 12 kg Korean rockfish, which were fed approximately $0.5\%$ of the total fish body weight daily. During the 2-month culture period, total ammonia nitrogen (TAN) and nitrite nitrogen $(NO_2-N)$ concentrations remained below 1mg/L and 2mg/L, respectively. The chemical oxygen demand (COD) fluctuated between 13.6 and 31.2 mg/L on selected sampling days. The total suspended solids (TSS) removed by the foam fractionator was between 2.7 and 4.6g daily. The Styrofoam bead filter not only reduced TAN and $NO_2-N$ in the culture tank water, but also trapped solids equivalent to 8.3-26.7\% of the weight of feed supplied. In Trial 2, 30kg of live fish were held in the aquarium without feeding for a 24-hour period and the water quality parameters were monitored. TAN and $NO_2-N$ concentrations first increased and then decreased to around 0.3mg/L. These results demonstrate that the recirculating aquarium system is a functional option for the short-term culture or holding of marine fish.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.221-222
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• 2003

Typically, closed production system units are subject to an accumulation of fine suspended solids and dissolved organics (Weeks et at., 1992). Foam fractionation process is believed to be most effective in marine application for solids removal. In present experiment, the performance of foam fractionator for removal of solids, protein, and other dissolved materials was evaluated at different foam overflow heights and air flow rates in a pilot-scale recirculating aquaculture system for culture of Korean rockfish. (omitted)

• 한국식품과학회지
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• 제40권3호
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• pp.251-256
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• 2008

한국의 전통 한국의 전통적인 식품 중, 대표적인 장류로서 반가 식품에 해당하는 수조육류와 어패류를 첨가하여 제조한 어육장(규합총서의 방법)을 발효시키되, 2달 간격으로 발효기간에 따라 ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, lipase, lipoxygenase 및 protease의 활성을 각각 측정하여 경시적 변화를 관찰하였다. 어육장을 액체와 고체시료로 나누어 이상에서 열거한 효소들의 활성을 측정한 결과, lipase 및 lipoxygenase의 비활성도는 모두 0.05unit/mg protein 이하로서 효소 활성도가 낮은 수준이었으며, 1년동안의 발효·숙성기간 중 비활성 증감변화도 미미하였다. 반면,${\alpha}$-amylase, esterase, ${\beta}$-glucosidase 및 protease는 숙성기간에 따라 효소의 활성이 증가하는 것을 확인할 수 있었고, 특히 10개월째에는 액체시료의 경우 4종류 효소의 비활성이 급격히 증가하였다가 감소하는 것을 확인할 수 있었다. 전반적으로 고체시료의 단백질 함량은 액체시료보다 높았지만, 액체시료의 비활성이 고체시료보다 2-5배 이상 높은 결과를 확인하였다.

• Environmental Engineering Research
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• 제20권4호
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• pp.377-382
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• 2015

The high concentration of nitrogen and phosphorus in wastewater incorporated with the ability to use carbon dioxide as the carbon source make the microalgae become more attractive in wastewater treatment process. This study evaluates the optimal conditions for the digestion of settelable solids from the recirculating aquaculture system to produce the biomass of the green microalga Scenedesmus sp. After solids separation, aerobic digestion of settleable solids under disperse condition produced nitrate as the final product of consequently ammonification and nitrification processes. With the optimal digestion procedure, nitrate concentration during aerobic digestion in 2000 mL vessel increased from $9.63{\pm}0.65mg\;N/L$ to $58.66{\pm}0.06mg\;N/L$ in 10 days. Thereafter, cultivation of Scenedesmus sp. was performed in 1000 mL Duran bottle with air bubbling. The highest Scenedesmus sp. specific growth rate of $0.321{\pm}0.01/d$ was obtained in treatment using liquid fraction after aerobic digestion as the whole culture medium for Scenedesmus sp. cultivation. With this study, digestion of $8,800{\pm}128.12mg\;dry\;weight/L$ of settleable solids from fish pond finally produced $1,235{\pm}21mg\;dry\;weight/L$ of Scenedesmus sp. biomass.

• Ocean and Polar Research
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• 제26권1호
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• pp.102-111
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• 2004

Recirculating aquaculture system (RAS) consists of different treatment compartments that maintain water quality within the ranges commonly recommended for fish cultures. However, common RASs still exert considerable environmental impact since concentrations of organic matter and nutrients in their effluents are high. Compared with the traditional RAS, the model RAS developed here use a sedimentation basin for digestion purposes and then use the released volatile organic matter to stimulate a denitrification process. Different treatment compartments for solids, total ammonia nitrogen, and nitrate removal have been reviewed. This paper provides the basic information on designing different treatment compartments as well as the engineering criteria in closed seawater RAS, consisting of circular tanks for fish cultures; dual drain systems, sedimentation basins and foam fractionators for removal of solids; nitrification biofilters for TAN removal; denitrification biofilters for nitrate removal; and aerators for aeration. The main purpose is to outline a common procedure in designing of closed RAS for marine fish culture with an emphasis on easy management and low expense, as well as reduction of the environmental impact.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.133-139
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• 2010

The effects of suspended solids size on culture water quality were determined in a commercial recirculating aquaculture system (RAS) for Japanese eel, Anguilla japonica. The particulate phase of the culture water was serially divided into six size fractions using 300, 200, 100, 75, 45, and 26 ${\mu}m$ pore size stainless sieves. The total, dissolved, and particulate nitrogen and phosphorus, and suspended solids for each fraction were determined. The concentration ranges in the fractions were: total nitrogen, 164-148 mg $L^{-1}$; total phosphorus, 20.4-15.5 mg $L^{-1}$; and total suspended solids, 8.1-6.1 mg $L^{-1}$. The concentration of total nitrogen and total phosphorus decreased significantly (P<0.05) with a 26 ${\mu}m$ and 200 ${\mu}m$ filter pore size, respectively. Nutrients from dissolved organic substances were much higher than from particulates. Analysis of particle size fractionation and its effects on water quality is useful to estimate removal efficiencies of a commercial effluent screening device for solid management and development of solid removal systems.

• 한국양식학회지
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• 제21권3호
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• pp.181-183
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• 2008

It has been a very hard problem to reduce solids especially suspended solids (SS) in recirculating aquaculture systems. Present description is based on the performance of trapping SS by the biofilter of Intensive Bio-production Korean (IBK) system which is originally developed for nitrification. We found out that this filter has an excellent capability to remove SS in addition to nitrification. Filter element used here is corrugated plastic roofing plates readily available in the market, and cheaper than specially developed and patented products. It is easy to maintain the system, and requires low power consumption to operate for the treatment of a large amount of water. With 2 pumps of 5 hp each, about 500 $m^3$ of water is treated per hour. Flow speed in the filter was 2.6 mm/sec on average. This low flow speed and very large amount of water treated are the reasons for very effective trapping of fine SS. Upon single pass through this filter, 74.5% of total SS and 40% of non-settleable SS were removed. Wherever this filter is employed in recirculating fish farms water keeps high clarity, this having also been empirically ascertained.

• Environmental Engineering Research
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• 제10권2호
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• pp.79-87
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• 2005

The effects of transformation capacity on cometabolic degradation of trichloroethene (TCE) were evaluated using TCE-degrading actinomycetes pure and mixed culture under various culture conditions. The TCE transformation capacity of the actinomycetes enrichment culture in a batch test with phenol addition was 1.0 mg of TCE/mg of volatile suspended solids (VSS). The resting cell TCE transformation capacity of the actinomycetes pure culture cell was 0.75 mg TCE/mg VSS, which increased to 2.0 mg TCE/mg VSS when phenol was added as an external substrate. When the pure culture had an internal substrate in the form of poly-β-hydroxybutyrate (PHB) at 19% of the cell mass, the resting cell TCE transformation capacity increased from 0.47 to 0.6 mg TCE/mg VSS. The presence of PHB increased transformation capacity by 57%, whereas, the addition of phenol caused more than two fold increase in transformation capacity. The actinomycetes culture showed the highest transformation capacity.

• 한국화재소방학회논문지
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• 제23권5호
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• pp.9-16
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• 2009

최근 급속히 발전하고 있는 과학기술과 산업발달에 따라 화학물질, 위험물의 사용, 저장 및 운송물이 날로 증가하고 있다. 이러한 물질들은 우리의 일상생활과 인류문화 발전에 크게 기여하고 있지만 인화성, 폭발성 등의 잠재위험성을 가지고 있다. 세계 각국은 물질의 분류와 표시가 달라 국제무역에서 많은 사고가 증가하고 있는 실정이다. 이 연구의 목적은 위험물에 대한 국제적인 시험방법을 개발하는 것이며 시험데이터를 기준으로 선택가능방식(Building Block Approach)으로 분류하고자 한다. 국내 위험물안전관리법에서는 위험물을 산화성고체, 가연성고체, 자연발화성물질 및 금수성물질, 인화성액체, 자기반응성물질, 산화성액체로 분류하고 있다. 1차적으로 산화성고체 35종에 대하여 위험물안전관리법에 의한 시험방법, UN시험방법으로 시험한 데이터를 비교하여 이들의 연관성을 도출하고, 국제적으로 분류하여 국내실정에 적합한 산화성고체 시험방법을 제시하였다.

• 한국식생활문화학회지
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• 제38권5호
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• pp.345-355
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• 2023

This study was conducted on four types of laver soup prepared using recipes from Gangwon-do (GW), Gyeongsangnam-do (GN), Jeollanam-do (JN), and the media (MD). Salinities, soluble solids, free amino acids, color values, turbidities, and pH values of soups were measured, and sensory evaluations were done. pH values were significantly higher for GW and GN recipes than the JN and MD recipes (p<0.05). The salinities of JN and MD were significantly higher than those of the other soups (p<0.05). Regarding soluble solids, JN had the highest at 2.64°Brix, whereas GW had the lowest at 0.86 °Brix (p<0.05). GW and JN had higher concentrations of valine, phenylalanine, and glutamic acid (p<0.05). JN had significantly higher redness (a) than the other soups but significantly lower lightness (L) and yellowness (b) (p<0.05). Regarding transmittance, GW had a significantly higher value (67.67%T) than the other soups. JN and MD had higher acceptability results than GW or GN in terms of flavor, mouthfeel, and overall acceptability. Sensory intensity evaluations revealed that JN and MD had higher "soy sauce aroma" and "saltiness" and a greater "broth turbidity" than the other soups. These results indicate that the physicochemical and sensory characteristics of regional laver soups differ.