• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.2
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• pp.95-101
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• 1989

For the utilization of polyunsaturated fatty acids in sardine (Sardinops melanosticta) oil, mainly as a source for dietary supplement of eicosapentaenoic acid(EPA) and docosahe-xaenoic acid(DHA), the effects of refining and storage, conditions, and addition of stabili-zing agents on the storage stability of EPA condensed and refined sardine oil were tested. Refined, sardine oil deacidified, decolored, and deodorized, was more stable to autoxidation than crude or partially purified oils such as deacidified or/and decolored. The refined sardine oil must be kept at $5^{\circ}C$ or lower temperture for longer than two month storage. The addition of $0.018\%\;\alpha-tocopherol$ or BHT could enhance the stability to autoxidation, and EDTA or citric acid was useful as synergist. Especially the addition of $0.02\%$ citric acid to the oil still hot after deodorizing process ($125^{\circ}C$) was of benefit to stabilize the refined oil.

• Environmental Analysis Health and Toxicology
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• v.26
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• pp.2.1-2.7
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• 2011

Objectives: N-Nitrosodimethylamine (NDMA) is classified as a probable human carcinogen by the United States Environmental Protection Agency (US EPA) and is formed during the chlorination of municipal drinking water. In this study, selected nitrosamines were measured in chlorinated drinking water collected from Chuncheon, Kangwon-do, Republic of Korea, and a risk assessment for NDMA was conducted. Methods: Twelve water samples were collected from 2 treatment plants and 10 household taps. Samples were analyzed for 6 nitrosamines via solid-phase extraction cleanup followed by conversion to dansyl derivatives and high-performance liquid chromatography-fluorescence detection (HPLC-FLD). Considering the dietary patterns of Korean people and the concentration change of NDMA by boiling, a carcinogenic risk assessment from ingestion exposure was conducted following the US EPA guidelines. Results: NDMA concentrations ranged between 26.1 and 112.0 ng/L. NDMA in water was found to be thermally stable, and thus its concentration at the end of boiling was greater than before thermal treatment owing to the decrease in water volume. The estimated excess lifetime carcinogenic risk exceeded the regulatory baseline risk of $10^{-5}$. Conclusions: This result suggests that more extensive studies need to be conducted on nitrosamine concentration distributions over the country and the source of relatively high nitrosamine concentrations.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.1026-1034
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• 2014

This study was conducted to assess the effects of flaxseed oil and dried whitebait as a source of ${\omega}$-3 fatty acids (${\omega}$-3 FA), which could be used to produce eggs enriched with ${\omega}$-3 FA, and of fructo-oligosaccharide (FOS) as a source of prebiotics on performance of hens (commercial Hy-Line Brown laying hens), and FA composition, internal quality, and sensory characteristics of the eggs. Dietary FOS increased egg weight. The amounts of ${\alpha}$-linolenic (ALA), eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) in the eggs from the hens fed the flaxseed oil alone or flaxseed oil+dried whitebait diets were higher than those of the control. Hedonic scores for off-flavor, fishy flavor, buttery taste and overall acceptability of the eggs from the hens fed the diet containing flaxseed oil+dried whitebait were lower (p<0.05) than those of the control. Overall acceptability of the eggs from the hens fed the diet containing soybean oil+dried whitebait was lower (p<0.05) than that of the control. However, all the sensory attributes of the eggs from the hens fed the diet containing flaxseed oil, dried whitebait and FOS were not significantly different from those of the control. These results confirmed that flaxseed oil increases the ALA content in the eggs and a combination of flaxseed oil and dried whitebait increases EPA and DHA in the eggs. Of significance was that addition of FOS to the flaxseed oil+dried whitebait diet improves the sensory characteristics of the eggs enriched with ${\omega}$-3 FA.

• Water for future
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• v.26 no.3
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• pp.125-135
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• 1993

This study was conducted for two purposes. The first was the selection of the proper model for the urban runoff, and NPS(non-point source) loads and the second was the adjustment of the selected model through the calibration and the verification of the observed data on an urban drainage basin. The selected model for this study was the Storm Water Management Model(SWMM) developed and maintained by the US Environmental Protection Agency(EPA). In particular, the Runoff Block for the surface discharge and the Transport Block for the flow routing was used. The study basin is Youngdu basin, which is a typical developed urban drainage basin. The four rainfall events for the runoff and the two for the four NPS pollutants(SS, BOD, COD and TN) were used for the calibration and the estimation of the model parameters. This study performed the calibration with regard to the peak discharge, the time to peak discharge, the volume and the relative error for three items. It was shown that SWMM can successfully be used for the prediction of the runoff and the NPS pollutants discharge. The result of this study can be used as the basis for the analysis of the correlation between the runoff and the NPS pollutants discharges, and the analysis of the mass balance with the monthly and annual NPS loads in an urban drainage basin.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.1035-1041
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• 2002

Ultrasonic nebulizer with the application of new engineering methodology and the design of electronic circuit and 766ppm Cd nebulizing solution were used to generate cadmium aerosol for inhalation toxicology study. The results of particle size analysis for cadmium aerosol were as following. The highest particle counting for source temperature 20℃ was 43.449 x 10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 50℃ was 43.211 x 10³ in inlet temperature 100 ℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 70℃ was 41.917x10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The ranges of geometric mean diameter(GMD) were 0.677-1.009㎛ in source temperature 20℃, 0.716-0.963㎛ in source temperature 50℃, and 0.724-0.957㎛ in source temperature 70℃. The smallest GMD was 0.677㎛ in source temperature 20℃ and inlet temperature 20℃. and the largest GMD was 1.009㎛ in source temperature 20℃ and inlet temperature 20℃. The ranges of geometric standard deviation(GSD) were 1.635-2.101 in source temperature 20℃. 1.676-2.073 in source temperature 50℃, and 1.687-2.051 in source temperature 70℃. The lowest GSD was 1.635 in source temperature 20℃ and inlet temperature 20℃, and the highest GSD was 2.101 in source temperature 20℃ and inlet temperature 200℃. Aerosol generated for cadmium inhalation toxicology study was polydisperse aerosol. The ranges of mass median diameter(MMD) were 1.399-5.270㎛ in source temperature 20℃. 1.593-4.742㎛ in source temperature 50℃, and 1.644-4.504㎛ in source temperature 70℃. The smallest MMD was 1.399㎛ in source temperature 20℃ and inlet temperature 20℃, and the largest MMD was 5.270㎛ in source temperature 20℃ and inlet temperature 200℃. Increasing trends for GMD, GSD, and MMD were observed with same source temperature and increase of inlet temperature. MMD for inhalation toxicology testing in EPA guidance is less than 4㎛. In our results. inlet temperature 20 and 50℃ in source temperature 20℃, and inlet temperature 20 to 150℃ in source temperature 50 and 70℃ were conformed to the EPA guidance. MMD for inhalation toxicology testing in OECD and EU is less than 3㎛. In our results, inlet temperature 20 and 50℃ in source temperature 20, 50, and 70℃ were conformed to the OECD and EU guidance.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.136-143
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• 2018

Cellular automata have been applied to simulations in many fields such as astrophysics, social phenomena, fire spread, and evacuation. Using cellular automata, this study develops a model for consequence analysis of the dispersion of hazardous chemicals, which is required for risk assessments of and emergency responses for frequent chemical accidents. Unlike in cases of detailed plant safety design, real-time accident responses require fast and iterative calculations to reduce the uncertainty of the distribution of damage within the affected area. EPA ALOHA and KORA of National Institute of Chemical Safety have been popular choices for these analyses. However, this study proposes an initiative to supplement the model and code continuously and is different in its development of free software, specialized for small and medium enterprises. Compared to the full-scale computational fluid dynamics (CFD), which requires large amounts of computation time, the relative accuracy loss is compromised, and the convenience of the general user is improved. Using Python open-source libraries as well as meteorological information linkage, it is made possible to expand and update the functions continuously. Users can easily obtain the results by simply inputting the layout of the plant and the materials used. Accuracy is verified against full-scale CFD simulations, and it will be distributed as open source software, supporting GPU-accelerated computing for fast computation.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.1
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• pp.83-96
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• 2005

The purposes of this study were to characterize the local levels of VOCs (volatile organic compounds), to develop source profiles of VOCs, and to quantify the source contribution of VOCs using the CMB (chemical mass balance) model. The concentration of VOCs had been measured every 6-day duration in the SRO monitoring site in the Yeosu Petrochemical Industrial Complex from September 2000 to August 2002. The total of 35 target VOCs, which were included in the TO-14 designated from the U.S. EPA, was selected to be monitored in the study area. During a 24-h period, the ambient VOCs were sampled by using canisters placing about 10 ～ 15 m above the ground level. The collected canisters were then analyzed by a GC-MS in the laboratory. Aside from ambient sampling at the SRO site, the VOCs had been intensively and massively measured from 8 direct sources and 4 general sources in the study area. The results obtained in the study were as follows; first, the annual mean concentrations of the target VOCs were widely distributed regardless of monitoring sites in the Yeosu Petrochemical Industrial Complex. In particular, the concentrations of BTX (Benzene, Toluene, Xylene), vinyl chloride were higher than other target compounds. Second, based on these source sample data, source profiles for VOCs were developed to apply a receptor model, the CMB model. Third, the results of source apportionment study for the VOCs in the SRO Site were as follows; The source of petrochemical plant was apportioned by 31.3% in terms of VOCs mass. The site was also affected by 16.7% from wastewater treatment plant, 14.0% from iron mills, 8.4% from refineries, 4.4% from oil storage, 3.8% from automobiles, 2.3% from fertilizer, 2.3% from painting, 2.2% from waste incinerator, 0.6% from graphic art, and 0.4% from gasoline vapor sources.

• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.122-128
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• 1996

Many computer programs have been developed for meteorological and air quality simulation. Many of the model the U.S. EPA recommends are available as. part of UNAMAP. HIWAY-II can be used to estimate the concentrations of nonreactive pollutants from highway traffic. As a result, It was found that distribution of concentration wind speed was 1 m/s to 5 m/s were diminished to about 1/2. In our study, we measured air pollutants(CO), temperature and humidity to evaluate. Meteorological parameter were influenced by not only wind direction but also vertical.

• Journal of Aquaculture
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• v.17 no.2
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• pp.151-157
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• 2004

Effects of supplementing selected fatty acids on fatty acid incorporation (17 days) , and progeny production (14 days) in Artemia franciscana (Great Salt Lake, USA) were studied. To compare with the control four diets, which differed in fatty acid composition alone contain Dunalieia tertiolecta and an emulsion either rich in OA (oleic acid, 18: 1 n-9), ARA (arachidonic acid, 20:4n-6), EPA (eicosapentaenoic acid,20:5n-3), or DHA (docosahexaenoic acid, 22:6n-3). Each of these emulsions was supplemented at a ratio of 20 % of the daily dose of D. tertiolecta (% algal dry weight). The initial OA and ARA values were 33.5 and 1.7 mg/g DW of freshly-hatched nauplii, respectively. After 11 days of feeding, these values increased to 38.8 and 7.6 mg/g DW in Artemia receiving the fatty acid sup-plement rich in each of the respective fatty acids. After 14 days, the levels were almost doubled, reaching 62.8 and 13.4 mg/g respectively. On EPA supplementation, its level after 11 days of feeding was 14.3 and 17.3 mg/g in male and female, respectively and was 16.0 and 23.1 mg/g in the male and female after 14 days, respectively. The EPA accumulated more in the body (39.1 mg/g) than in ovisac (16.9 mg/g). In the DHA supplementation group also, DHA levels after 11 days of feeding were 3.1 and 5.5 mg/g in male and female, respectively. After 14 days, the DHA level continued to increase in male. but slightly decreased to 4.6 mg/g in female. It was not richer in ovisac (2.6 mg/g) than in the remaining body of female (4.6 mg/g). In conclusion, fatty acids supplied by a lipid emulsion as a supplement to the algal diet are well incorporated in the adult Artemia. Apart from being an extra source of energy, these emulsions may function as source of HUFA which may play an essential role for growth and progeny production (fecundity) of Artemia.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.67-72
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• 1998

As a part of basic investigation for utilizing by-products derived from seafood processing as a food source, a chemical characteristics of fish bones (cod bone, Alaska pollack bone, yellowfin sole bone, hoki bone, conger eel bone and mackerel bone) were investigated. The crude protein (40.7% on the dry basis) and collagen contents (5.86%, on the dry basis), imino acid composition (189 residues/1,000 residues) of hoki bone were higher than those of the other fish bones, but were lower than those of the animal bone. The crude lipid contents and EPA and DHA compositions of yellowfin sole, conger eel and mackerel bones were $22.8{\sim}43.9%$ on the dry basis and $15.6{\sim}23.8%$, respectively and were lower than those of squid viscera. The major ash components of the fish bones were found to be calcium and phosphorus and the contents in 100 g crude ash were $37.1{\sim}38.6%$ and $18.0{\sim}18.5%$ respectively. The calcium and phosphorus contents in 100 g crude ash of cod and Alaska pollack bones were more than those of the animal bones, as well as the others. It may be concluded, front these results, hoki bone can be effectively utilized as a processing materal of collagen or gelatin and cod and Alaska pollack bones as a calcium source.