• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.436-445
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• 1986

As the second part of the studies on the utilization of polyunsaturated lipids in sardine oil as nutritional or medical supplement, the conditions of lipid extration and concentration, refining, and storage stability of EPA-condensed sardine oil were investigated. In extraction of lipids, solvent ratios of chloroform-methanol mixture(2:1 v/v) affected the final content of unsaturated lipid in extracted oil and recovery. Stepwise solvent fractionation method at various low temperatures was effective to concentrate polyenoic acids like EPA and DHA when acetone or acetone-methanol mixture, added in the ratio of 1:5 (v/v) was applied step by step to different temperatures at 0 to $-35^{\circ}C$. Addition of 1 to $5\%$ (v/v) of water to acetone was also benefit to raise EPA content but that resulted in reducing the yield of condensed oil from $65\%\;to\;28\%$. Concentration rate of polyenoic acids by solvent fractionation in lipid-actone solution (1:5, v/v) at 0 to $-30^{\circ}C$ seemed limited to $5{\sim}8\%$ in fatty acid composition depending on the initial content of those polyenoic acids in the sardine oil. During the extraction, concentration, and alkaline treatment, oxidation was rapidly induced but oxidation products could be thoroughly removed on the process of deceleration and peroxide elimination. To stabilize the reactive polyenoic acid condensed oil during the storage, stuffing nitrogen gas was essential to expel dissolved oxygen in oil or to seal the oil from open air, and the addition of antioxidative agents as BHA and tocopherols were greatly helpful to extend the storage life.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.269-280
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• 2018

This paper reports the results of field evaluation to determine the levels of heavy metals in major industrial complexes in Korea over a seven year period (2007~2013). The measurement of heavy metal was conducted using quartz fiber filter sampling and ICP-AES analysis. In order to validate the analytical performance of these methods, studies were also carried out to investigate data quality control(QC) parameters, such as the method detection limit (MDL), repeatability, and recovery efficiencies. The average concentrations of total suspended particulates (TSP) for the nine industrial complexes in Korea were $104{\sim}169{\mu}g/m^3$, which was higher than other industrial complexes and urban areas. The Sihwa and Banwol industrial complexes were shown to be the biggest contributing sources to high TSP emission ($159{\mu}g/m^3$ and $169{\mu}g/m^3$, respectively). The concentrations of heavy metals in TSP were higher in the order of Fe>Cu>Zn, Pb, Mn>Cr, Ni, As and Cd. It was observed that Fe was the highest in the Gwangyang and Pohang steel industrial complexes. The concentrations of Zn and Pb were high in Onsan, Sihwa and Banwol industrial complexes, and this was attributed to the emission from the nonferrous industry. Additionally, Cr and Ni concentrations were high in the Sihwa and Banwol industrial complexes due to plating industry. On the other hand, Ulsan and Onsan industrial complexes showed high Cr and Ni concentrations as a response to the emission of metal industry related to automobile. The correlation analysis revealed the high correlation between Cr and Ni in plating industry from Sihwa and Banwol industrial complexes. Adding to this, components related to coal combustion and road dust showed high correlation in Pohang and Gwangyang industrial complexes. Then Onsan and Ulsan industrial complexes showed high correlation among components related to the nonferrous metals.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1108-1113
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• 2005

Advanced oxidation process involving $O_3/H_2O_2$ was used to eliminate 1,4-dioxane and to enhance the biodegradability of dioxane-contaminated water. Oxidation process was carried out in a bubble column reactor under different pH and $H_2O_2$ concentrations. The removal efficiencies of 1,4-dioxane were investigated at hydrogen peroxide concentration between 40 and 120 mg/L. At the same pH, removal efficiencies of 1,4-dioxane increased with increasing initial $H_2O_2$ concentration. There was a linear relationship between initial concentration of $H_2O_2$ and the amount of consumed $O_3$. It was observed that the high $H_2O_2$ concentration accelerated the generation of hydroperoxy ions(${HO_2}^-$) and hydroxyl radicals($OH{\cdot}$). Hydrogen peroxide enhanced the decomposition of 1,4-dioxane and the biodegradability of the solution.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.149-159
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• 2011

Bentazone is benzothiadiazole group herbicide, and used to foliage treatment. This herbicide have already been widely used for cereals and vegetables planting in worldwide. This experiment was conducted to establish a determination method for bentazone residue in crops using HPLC-UVD/MS. Bentazone residue was extracted with acetone (adjusted pH 1 with phosphoric acid) from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover bentazone from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The bentazone was quantitated by HPLC with UVD, using a YMC ODS AM 303 ($4.6{\times}250$ mm) column. The crops were fortified with bentazone at 3 levels per crop. Mean recovery ratio were ranged from 82.0% for a 0.2 mg/kg in apple to 97.9% for a 0.02 mg/kg in Chinese cabbage. The coefficients of variation were ranged from 0.5% for a 0.02 mg/kg in soybean to 9.7% for a 0.02 mg/kg in Chinese cabbage. Quantitative limit of bentazone was 0.02 mg/kg in representative five crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of bentazone in agricultural commodities.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.125-133
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• 2011

Ametryn is used in USA, China, and Japan, but not introduced in Korea yet. So, MRL (Maximum Residue Level), and analytical method of ametryn were not establishment in Korea. Therefore, this experiment was conducted to establish a determination method for ametryn residue in crops using HPLC-UVD/MS. Ametryn residue was extracted with acetone from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover ametryn from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The ametryn was quantitated by HPLC with UVD, using a Tosoh ODS 120T ($4.6{\times}250$ mm) column. The crops were fortified with ametryn at 2 levels per crop. Mean recovery ratio were ranged from 83.7% for a 0.2 mg/kg in soybean to 91.1% for a 1.0 mg/kg in hulled rice. The coefficients of variation were ranged from 1.2% for a 1.0 mg/kg in hulled rice to 3.6% for a 1.0 mg/kg in soybean. Quantitative limit of amatryn was 0.02 mg/kg in representative 5 crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of ametryne in agricultural commodities.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.353-359
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• 2009

Interest in marine organisms as potential sources of bioactive agents has increased in recent years. The red seaweed, Callophyllis (C.) japonica, is abundant in the coastal regions of Jeju Island in South Korea. A previous study shows that C. japonica extracts have antioxidant activity and radioprotective effects. In this study, an methanol extract of C. japonica was tested whether it has antibacterial effects against the bacteria from swine. In vitro antibacterial activities of the crude extracts prepared from the C. japonica using 80 % methanol were tested for inhibitory activity against the Escherichia (E.) coli (S175), Enterococcus (E.) faecium (ATCC 51558), Salmonella (S.) Typhimurium and Staphylo-coccus (S.) aureus (ATCC 25923) by using broth dilution method. All organisms were incubated in brain heart infusion medium containing 1% extract at 0, 4, 8, 12 and 24 hrs. The 3 days-old piglets were fed an experimental diet supplemented with 1% C. japonica for 1 week. And the change of the coliform bacteria in feces were examined after supplement of C. japonica for 1 week. When the inocula containing $10^2{\sim}10^3$CFU/ml of each organism were used the extracts of C. japonica showed various degrees of antibacterial effects on all bacteria tested. The CFU value ($6.3\times10^8$CFU/ml) of C. japonica for E. coli was decreased 30% compared with vehicle controls ($9.0\times10^8$CFU/ml) after 8 hrs incubation. The proliferation rate of E. faecium was inhibited about 68% at 4 hrs, 81% at 8 hrs and 76% at 12 hrs after incubation, respectively. The proliferation rate of S. Typhimurium was inhibited about 96% at 4 hrs, 90% at 8 hrs and 72% at 12 hrs after incubation with extracts of C. japonica. The proliferation rate of S. aureus was inhibited more than 90% each time courses. Conclusively, a red seaweed extract of C. japonica was found to be effective against a number of gram negative and gram positive bacteria such as E. coli, E. faecium, S. Typhimurium, and S. aureus. The number of coliform bacteria was increased in the 1% C. japonica-treated group, as compared to those of controls. This result suggests that C. japonica extracts be added as an effective natural antibacterial agent. The precise mechanism of antibacterial effects and its application on swine industry remains to be further studied.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.337-349
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• 2016

In this study, an analytical method to evaluate the quality of isoflavonoid compounds purified and isolated from the fruits of Cudrania tricuspidata was developed and validated using Ultra Performance Liquid Chromatography (UPLC). The fruits of C. tricuspidata were extracted with methanol and further fractioned with n-hexane, ethyl acetate and water. The resulting ethyl acetate extract separated into four isoflavonoid compounds by a combination of silica gel and sephadex LH-20 column chromatography. The structures of the compounds were elucidated as alpinumisoflavone, 6,8-diprenyl genistein, 6,8-diprenyl orobol, 4'-O-methylalpinumisoflavone by various techniques such as UV-Vis, ESI-MS, $^1H\;NMR$ and $^{13}C\;NMR$ spectroscopy. Finally, a method to characterize the compounds was developed by using the UPLC equipped with a $C_{18}$ column and a gradient mobile phase system consisting of 2% acetic acid in water (solvent A) and 2% acetic acid in methanol (solvent B). The developed method was validated with the parameters such as selectivity, linearity, limit of detection, limit of quantitation, accuracy, and precision, which are defined by the ICH (International Conference on Harmonization). Using the validated method, the compounds in the fruits harvested in different months were also quantitatively analyzed. We propose this approach this approach can readily be utilized as an efficient evaluation method to quantify the extracts of C. tricuspidata.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.21-28
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• 1984

The milling property of ti different Australian Wheat varieties (Australian Prime Hard (APH), Australian Hard (AH), Western Australian Wheat (WAW), South Australian Wheat (SAW), Australian Standard White (ASW) and Australian Soft Wheat (SW) was investigated by using $B{\ddot{u}}hler$ test mill. The flour characteristics were evaluated by farinograph, mixograph, amylograph, sedimentation and pelshenke tests. The milling race of Australian wheats varied from 59% to 66%, and that of Suwon 219 (Korean variety) was 65.5%. The milling rate was significantly related to the seed weight but less extent to the bulk density of grain. The flours obtained from the wheat varieties exhibited distinctly different chemical compositions and dough properties. The protein content of the flour varied from 14.47% (APH) to 6.59 % (SW). The gluten forming ability of APH and AH was very high, but very low with ASW and Sw. On the other hand, ASw and WAW showed very high gelatinized viscosity, while SAW marked exceptionally low viscosity.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2006.05a
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• pp.211-216
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• 2006

교통주제도는 건설교통부와 한국교통연구원이 ${\ulcorner}$국가교통DB구축사업${\lrcorner}$의 일환으로 제작한 것으로, 국토지리정보원의 NGIS 수치지도(축척 1:5,000)를 기반으로 하여 현장조사 및 문헌조사를 통해 갱신, 보완하여 교통 분야의 활용에 적합하도록 구축한 GIS 수치지도이다. 교통주제도는 현장조사와 문헌조사를 통해 수집된 자료를 기반으로 구축되며 이중 교통시설물조사는 문헌자료(준공도로현황 등)를 참고하여 산정된 조사대상에 대하여 GPS 조사시스템을 활용, 도형 및 속성정보를 취득하는 것을 말한다. 조사항목은 도형정보(노드, 링크) 및 속성정보(차선수, 도로번호 등)이며 GPS 조사시스템과 조사원장(도면)을 이용하여 조사한다. 교통시설물조사와 문헌자료조사를 통해 수집된 자료는 단위도엽(1:5,000기준)별로 교통주제도에 반영되며 최종적으로 전국단위의 통합자료로 구축된다 교통주제도는 사용목적과 축척기준에 따라 단순화되며 이를 교통주제도 레벨이라 한다. 교통주제도의 레벨은 총 4단계로 구분되며 현재 레벨2에서 레벨4까지 구축되고 있다. 교통분석용 네트워크는 교통시설투자계획, 수요분석, 타당성 평가와 같은 교통분야의 연구를 수행하기 위해 반드시 필요한 자료이다. 교통분석용 네트워크는 교통주제도보다 더 단순화된 도로망 모델로서 구성요소는 노드(시점, 종점, 죤 센트로이드)와 링크(도로망, 센트로이드 커넥터)이며 도로의 기하구조보다는 논리적 구조(방향성, 노드/링크 연결성 등)에 중점을 둔 데이터이다 교통분석용 네트워크는 교통주제도의 도형과 속성정보를 기반으로 하며 각종 통계자료(도로교통량통계연보 등)를 활용, 구축된다. 교통분석용 네트워크는 구축시점에 따라 현재 및 장래 네트워크로 구분되며 장래 네트워크는 기준년도부터 2031년까지 5년 단위로 계획된 장래도로를 반영하여 구축된다. 교통주제도 및 교통분석용 네트워크는 국가교통DB구축사업을 통해 구축된 자료로서 교통체계효율화법 제9조의4에 따라 공공기관이 교통정책 및 계획수립 등에 활용할 수 있도록 제공하고 있다. 건설교통부의 승인절차를 거쳐 제공하며 활용 후에는 갱신자료 및 활용결과를 통보하는 과정을 거치도록 되어있다. 교통주제도는 국가의 교통정책결정과 관련분야의 기초자료로서 다양하게 활용되고 있으며, 특히 ITS 노드/링크 기본지도로 활용되는 등 교통 분야의 중요한 지리정보로서 구축되고 있다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.5
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• pp.46-54
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• 2011

In this paper, we propose a low-complexity loop filtering method depending on transform-block regions. Block adaptive loop filter (BALF) was developed to improve about 10% in compression performance for the next generation video coding. The BALF employs the Wiener filter that makes reconstructed frames close to the original ones and transmits filter-related information. However, the BALF requires high computational complexity, while it can achieve high compression performance because the block adaptive loop filter is applied to all the pixels in blocks. The proposed method is a new loop filter that classifies pixels in a block into inner and boundary regions based on the characteristics of the integer transform and derives optimum filters for each region. Then, it applies the selected filters for the inner and/or boundary regions. The decoder complexity can be adjusted by selecting region-dependent filter to be used in the decoder side. We found that the proposed algorithm can reduce 35.5% of computational complexity with 2.56% of compression loss, in case that only boundary filter is used.