• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.95-95
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• 2018

강재의 방식법 중 도장은 부식을 억제하는데 효과적이고 편리한 방법으로 선박 및 해양 강 구조물의 방식법으로 사용되고 있다. 한편, 강 구조물의 효율적인 유지관리를 위해서는 방식 도장의 도막 열화도를 평가하고 잔존 수명을 예측하여 최적 시기에 보수도장 혹은 재도장하는 것이 필요하다. 일반적으로 선박 및 해양구조물에 적용되는 도막의 방식 성능 평가 방법으로 해수 침지 시험, 염수 분무 시험, 옥외 폭로 시험 등이 있다. 그러나 이러한 시험들은 그 시험 방법에 따라서 정량적인 평가에 한계가 있음은 물론 장기간 소요되는 등 곤란한 문제점이 있다. 그러므로 선박 및 해양구조물을 비롯하여 교량, 각종 강 구조물의 도장 방식에 사용되는 방식용 도료의 성능을 단기간에 적절하게 평가할 수 있는 가속시험법이 제시되며 연구-사용되고 있다. 그 중 도막 방식 성능을 보다 효율적, 비파괴적, 정량적으로 평가할 수 있는 임피던스 분광법(EIS)과 같은 전기화학적 방법은 상대적으로 시험 기간을 크게 단축시킬 수 있고, 대상 방식 도장의 미세한 성능 차이도 분별 가능하다는 장점이 있다[1]. 따라서 본 연구에서는 선박 및 해양구조물 등 가혹한 부식환경에서 강력한 내구성을 가질 수 있도록 다양한 종류의 표면처리 도장 시편을 제작하여 자외선 조사-염수분무-침지환경 등의 열악한 환경조건 하에서 부식-열화 촉진 시험을 실시하였다. 그리고 그 촉진 열화 과정에서 도막의 외관 상태를 관찰 분석함은 물론 전기화학적 임피던스 분광법을 병행 측정하며 그 표면막의 부식 및 도막 열화도를 비교-종합 평가하였다.본 연구에 사용된 시편은 Al 및 Zn 도금 강판에 에폭시, 에폭시-실리콘 우레탄, 에폭시-우레탄 도장 시편으로 Scribe, No Scribe 및 비교재 Al 및 Zn 도금 시편으로 분류하여 각각 실험을 진행하였다. 즉, 도막 열화 시험은 복합 노화 시험법으로 UV 조사 36 시간(ASTM G53), 염수분무 32 시간(ISO 7253), 수분 응축 10 시간을 1 Cycle로 100 Cycle(7800 시간) 동안 실험을 진행하였다. 이때 도막 열화도 평가는 전기화학적 임피던스 분광법을 이용하여 각 실험 조건별로 주파수에 따른 임피던스(Z) 값을 평가하였다. 즉, 상온 $25^{\circ}C$의 3.5% NaCl 100 ml 수용액에 작동 전극(Working Electrode)과 구리 도선을 통해 연결하였고, 노출 면적은 $1cm^2$로 일정하게 유지 하였으며, 상대 전극(Counter Electrode)은 탄소봉, 기준 전극(Reference Electrode)으로 포화카로멜전극(Saturated Calomel Electrode)을 사용하여 측정하였다. No Scribe 시편의 경우에는 Al 기판 에폭시-실리콘 우레탄 도장 시편이 우수한 도막 저항성을 나타내었으며, 에폭시-우레탄 도장시편은 23사이클 이후의 저항값이 가장 낮게 나타났다. Zn 기판의 경우는 에폭시, 에폭시-실리콘 우레탄, 에폭시-우레탄 도장 시편 모두 저항 값이 유사하였으며, Al 및 Zn 도금 시편은 도장 처리된 시편에 비해 훨씬 낮은 저항 값을 보였다. 또한 Scribe 시편의 경우에는 Al 기판 에폭시-실리콘 우레탄 도장 시편에서 높은 초기 저항 값을 보였으며, 23 사이클 후의 저항 값은 세 종류의 도막에서 약 1~0.1 Gohm 으로 나타났다. 그리고 Zn 기판 에폭시-실리콘 우레탄 도장 시편에서 가장 낮은 도막 저항 값이 나타났다. 이상의 실험을 통해서 본 연구 내용은 실내촉진시험으로 선박 및 해양 강 구조물에 사용되는 다양한 종류의 도막의 열화도를 평가하는 기초 설계 지침으로 응용될 수 있을 것으로 사료된다. 한편, 도막은 노출 환경에 따라 방식 성능이 다르므로 실제 도막의 사용환경을 고려하여 도장 사양별 적용 부위에 따른 적정 가속 실험 방법을 선정할 필요가 있다고 사료된다.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.55-67
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• 2012

We compared the general composition of Mozzarella cheese manufactured by the traditional method and by an ultrafiltration technique. The comparison of the general components between raw milk and the retentate of ultrafiltration (CF 2 and CF 3) demonstrated the following. The fat, protein, and non-fat solid contents of the retentate were higher than those of raw milk, but the lactose content was lower. The effect of 3 factors-fat content (0.5% and 3%), bacterial populations (30,000 CFU/mL and 100,000 CFU/mL), and ratio of added starter and rennet (50, 65, or 80)-on Mozzarella cheese made by the traditional method and made using the retentate of ultrafiltration (CF 2 and CF 3) were compared. Total solids (TS), fat, lactose, total nitrogen (TN), water soluble nitrogen (WSN), non-protein nitrogen (NPN), and salt (NaCl) were affected by fat content, bacterial population, and the ratio of starter and rennet added, but the ash content was not affected. During storage at $4^{\circ}C$ over a period of 3 months, the TS, WSN, NPN, and NaCl contents increased significantly (p<0.05), but fat, lactose, and TN contents decreased significantly (p<0.05), while ash contents remained constant. In whey, the protein, lactose, and solids not fat contents were higher in cheese made from ultrafiltration retentate than in traditional Mozzarella cheese. These results indicate that ultrafiltration can be applied to producing several Mozzarella-type cheeses in order to meet consumer needs.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.442-448
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• 2012

Many outbreaks of food-borne illnesses have been associated with the consumption of fresh vegetables and fruits contaminated with food-borne pathogens. Contaminated medium, manure and irrigation water are probable vehicles for the pathogen in many outbreaks. The aim of this study was to determine the potential transfer of Escherichia coli and Bacillus cereus from medium and soil fertilized with contaminated compost or irrigation with contaminated water to the edible parts of lettuce. Moreover, survivals of the two pathogens on lettuce contaminated medium, soil and irrigation water were estimated. Lettuce seeds were planted in medium contaminated with 7.5 log colony forming unit (CFU)/g of E. coli and B. cereus. Seedlings grown in the contaminated medium were transplanted in soil fertilized with contaminated pig manure compost or uncontaminated soil. Contaminated irrigation water with E. coli and B. cereus at 8.0 log CFU/mL was applied only once on the plant by sprinkle irrigation and surface irrigation. Although E. coli and B. cereus in medium and sprouted lettuce after planting seeds were reduced as time passed, these pathogens survived in seedling raising stage for extended periods. The numbers of E. coli and B. cereus in lettuce grown on contaminated soil were detected over 4.0 log CFU/g for 21 days. The numbers of E. coli and B. cereus in lettuce applied by sprinkle irrigation were higher than those of surface irrigation by 5.0 log CFU/g. Our results indicated that contaminated medium, soil and irrigation water can play an important role in the presence of food-borne pathogens on vegetables.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.303-309
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• 2010

This study was planned to monitor the change in the content of sulfur dioxide during the drying process of fresh vegetables. The analysis of sulfur dioxide was conducted by the Optimized Monier-Williams Method based on the Korea Food Code. The samples were kinds of vegetables which consisted of naturally-originated sulfur compounds (green onion, onion, cabbage, garlic, radish leaves, radish). Fresh vegetables (n = 182) and dried vegetables (n = 41) purchased from different local areas were investigated for the content of sulfur dioxide. The fresh vegetables were dried at 50~$60^{\circ}C$ using hot-air dryer. The moisture contents of dried samples were adjusted to keep 10 percents. The contents of sulfur dioxide in self-dried vegetables were 104.6 mg/kg in green onion, 75.4 mg/kg in onion, 129.1 mg/kg in cabbage, 197.6 mg/kg in garlic, 23.0 mg/kg in radish leaves and 52.5 mg/kg in radish, respectively. The increase of sulfur dioxide content according to the moisture content reduction was different from the expected. It means that the contents of sulfur dioxide can be altered by other factors except moisture contents. This results can be utilized as materials for the safe management of sulfites of dried vegetables.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.701-707
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• 2008

Antidiabetic effect of Korean red ginseng (RG) processed by puffing in streptozotocin (STZ)-induced diabetic (DM) rats was investigated. Five week-old SD rats were divided into four groups; normal control (NC) group, DM group, red ginseng (RG) group and puffed red ginseng (PG) group. The RG and PG groups were orally provided with RG or PG dissolved in water (500 mg/kg) respectively for seven weeks after single injection of STZ (50 mg/kg, i.v.) followed by identification of DM. NC group received saline vehicle instead of STZ. At the end of feeding of RG or PG, the changes of fasting blood glucose, serum insulin and amylase level and serum lipid profiles were evaluated. Also, oral glucose tolerance test (OGTT), comet assay and histopathological examination were performed. At 7th week, the fasting blood glucose levels of the RG and PG groups were reduced compared to the DM group by 11.54% and 20.22%, respectively. The result of OGTT did not show significant differences among DM and two red ginseng groups. While serum insulin and TG levels were predominantly improved in PG group (p<0.05), serum amylase level was increased in RG group. Alkaline comet assay for checking the oxidative damage of DNA showed that TL (tail length, ${\mu}m$) and TM (tail moment) in the blood lymphocyte of PG group significantly decreased in contrast with DM group. Histopathological results of pancreas showed that destruction of exocrine as well as endocrine might be cured by the administration of RG and PG. These results suggest that PG could exert more protection against STZ-induced toxicity than RG group.

• Tuberculosis and Respiratory Diseases
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• v.71 no.3
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• pp.195-201
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• 2011

Background: Osteopontin (Opn) is recognized as an important adhesive bone matrix protein and a key cytokine involved in immune cell recruitment and tissue repair and remolding. However, serum levels of osteopontin have not been evaluated in patients with chronic obstructive pulmonary disease (COPD). Thus, the aim of this study was to evaluate and compare the serum levels of osteopontin in patients experiencing COPD exacerbations and in patients with stable COPD. Methods: Serum samples were obtained from 22 healthy control subjects, 18 stable COPD patients, and 15 COPD with exacerbation patients. Serum concentrations of osteopontin were measured by the ELISA method. Results: Serum levels of osteopontin were higher in patients with acute exacerbation than with stable COPD and in healthy control subjects ($62.4{\pm}51.9ng/mL$, $36.9{\pm}11.1ng/mL$, $30{\pm}11ng/mL$, test for trend p=0.003). In the patients with COPD exacerbation, the osteopontin levels when the patient was discharged from the hospital tended to decrease compared to those at admission ($45{\pm}52.1ng/mL$, $62.4{\pm}51.9ng/mL$, p=0.160). Osteopontin levels significantly increased according to patient factors, including never-smoker, ex-smoker and current smoker ($23{\pm}5.7ng/mL$, $35.5{\pm}17.6ng/mL$, $58.6{\pm}47.8ng/mL$, test for trend p=0.006). Also, osteopontin levels showed a significantly negative correlation with forced expiratory volume in one second ($FEV_1$%) predicted in healthy controls and stable COPD patients (r=-0.389; p=0.013). C-reactive protein (CRP) was positively correlated with osteopontin levels in patients with COPD exacerbation (r=0.775; p=0.002). Conclusion: The serum levels of osteopontin increased in patients with COPD exacerbation and tended to decrease after clinical improvement. These results suggest the possible role of osteopontin as a biomarker of acute exacerbation of COPD.

• Food Science and Preservation
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• v.13 no.6
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• pp.720-725
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• 2006

This study was conducted to investigate extracting solution effect on the chemical compositions in different parts of Korean mountain Ginseng. Water, 80% EtOH and 80% MeOH are used as extraction solutions, and extracting conditions were 2 hr at $85^{\circ}C$ in water bath. The Brix(%) of the extract were ranged from $0.42{\sim}22.58%$, 80% EtOH extract for leaf is the highest level as 22.58%. The pH ranges of the extracts were $4.43{\sim}7.41$ and brown color of the extract was the highest with 1.803 in 80% EtOH extract for leaf, respectively. In case of hunter's color value of the extract, L value is the highest with 24.35 in 80% EtOH extract of seed, a and b value were the highest with 0.41 in 100% water extract of leaf and 3.69 in 80% MeOH extract of stem. Sucrose is the major free sugar of the extinct it highest content with 3673 mg% in 80% MeOH extract of mot and fructose is the highest with 1897 mg% in 80% MeOH extract of leaf, Major organic acids are identified as malic, tartaric and citric acid, and total organic acid content is the highest with 5,254 mg% in 80% MeOH extract of leaf and 1,527 mg% in 80% EtOH extract of leaf, The extracted major minerals ate P and K, P content highest with 15,563 ppm in 100% water extract of stem, K is 4,952 ppm in 80% MeOH extract of leaf, and Ca is the highest with 3,052 ppm in 1011% water extract of leaf. These results suggest that extracting solvent (80% MeOH) is concerned with the extract preparation of Korea Mountain Ginseng.

• Clean Technology
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• v.26 no.2
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• pp.151-157
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• 2020

Rapid urbanization has elevated the risk of urban flooding due to the increase in the impervious surface, causing environmental disasters and environmental pollution problems, such as lowering the groundwater level and increasing water pollution. In Korea, low impact development (LID) techniques have been introduced to minimize these environmental impacts and maintain the water cycle soundness. However, most small-scale development projects are in blind spots because there is no legal basis for rainfall runoff management. Small-scale development projects that increase the surface runoff of rainwater are required to mandate the application of LID facilities in accordance with the polluters' responsibility principle. Therefore, it is necessary to implement a preliminary consultation system for water cycle recovery. This study focuses on the cost-benefit analysis on the application of LID techniques for small-scale development projects. The scale of nationwide small-scale development projects used for cost-benefit analysis were defined as buildings with a land area of more than 1,000 ㎡ or a total floor area of 1,500 ㎡. As a result of analyzing the cost-benefits from the installation of LID facilities, they were found to be much lower than the economic standard value of 1. This might be due to the high cost of facilities compared to the scale of the project. However, considering the overall environmental value of improving the water environment and air quality by the installation of LID facilities and the publicity of reducing the operating cost of sewage treatment facilities, the introduction of a prior consultation for small-scale development projects is inevitable. In the future, institutional and financial support from local governments is required to improve the cost-benefits with the introduction of a prior consultation for small-scale development projects.

• Journal of Sasang Constitutional Medicine
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• v.18 no.3
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• pp.75-93
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• 2006

1. Objectives and Methods Sasang Constitutional Medicine is the original Korean Medicine. The purpose of this study was to objectify the diagnosis of Sasang Constitution. 212 Women's sentences were analyzed into 228 factors like Pitch, APQ, Shimmer, Octave and Energy, etc. Women's sentences were classified into 3 categories: total group, under 54 years old group and over 55 years old group. 2. Results 1) In Total group Soyangin's Center feq.(3) was significantly high compared with Taeyangin and Taeumin groups. Taeumin's Pitch2 was significantly high compared with Soeumin and Taeyangin groups. Taeyangin's Pitch S.D. was significantly high compared with Soyangin group. Taeyangin's Octave6 was significantly high compared with Soeumin group. There were no significant differences among constitutional groups in APQ and Shimmer segment. On the point of Energy, Taeyangin's G Tot E(1), G# Tot E(1), G dev.(1), G# dev.(1), G Tot E(2), G# Tot E(2), G dev.(4) and G# dev.(4) were significantly high compared with other groups. Soyangin's A#S.D.(2) was significantly high compared with Taeyangin group. Taeyangin's A#S.D.(3) was significantly high compared with Taeumin group. Taeyangin's F S.D.(5), F# S.D.(5) and Max Average were significantly high compared with Soeumin group. Taeumin's Peak3 and Peak4 were significantly high compared with Taeyangin group. Taeumin's PeakValue1 was significantly high compared with Soeumin group. Taeyangin's PeakValue2 was significantly high compared with Soeumin group. Taeyangin's PeakValue3 and PeakValue5 were significantly high compared with Other groups. 2) In Under 54 years old group, there were no significant differences among constitutional groups in APQ, Shimmer and Octave segment. Taeumin's Center freq.(2) was significantly high compared with Taeyangin and Soyangin groups. Taeumin's Pitch(2) and Pitch(3) were significantly high compared with Taeyangin and Soeumin groups. Taeyangin's and Taeumin's Pitch S.D. were significantly high compared with Soyangin group. Taeyangin's and Soyangin's Octave2 were significantly high compared with Taeumin group. On the point of Energy, Taeyangin's and Soyangin's A# S.D.(2) were significantly high compared with Soeumin group. Taeyangin's and Soyangin's G# dev.(1), G# dev.(2) were significantly high compared with Taeumin group. Taeyangin's and Taeumin's F# S.D.(3) were significantly high compared with Soeumin group. Taeyangin's and Soyangin's Max Average were significantly high compared with Soeumin group. Taeumin's Peak3 was significantly high compared with Taeyangin and Soeumin groups. Taeyangin's and Taeumin's PeakValue2 were significantly high compared with Soeumin group. Taeyangin's and Soeumin's PeakValue3 were significantly high compared with Taeumin group. Taeyangin's and Soyangin's PeakValue5 were significantly high compared with Soeumin group. Taeyangin's and Soyangin's PeakValue9 were significantly high compared with Taeumin group 3) In Over 55 years old group, there were no significant differences among constitutional groups in Pitch, APQ, and Peak segment. Soeumin's F Shimmer(1) and F Shimmer(2) were significantly high compared with Taeyangin and Taeumin groups. Soeumin's G# Shimmer(1) and G# Shimmer(2) were significantly high compared with Soyangin group. Taeyangin's Octave5 and Octave6 were significantly high compared with Soeumin group. On the point of Energy, Soyangin's C S.D., F# S.D.(1), F# S.D.(2) and G dev.(2) were significantly high compared with other groups. Soyangin's F# S.D.(3) was significantly high compared with Taeumin and Soeumin groups. Taeyangin's and Taeumin's G# S.D.(2) and G# S.D.(3) were significantly high compared with Soyangin group 3. Conclusions From above result, there is the possibility of efficient standard guide for constitution diagnosis by analysis of voice

• Journal of Life Science
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• v.23 no.5
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• pp.609-615
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• 2013

Glyceollin I has gained attention as a useful therapy for various dermatological diseases. However, the binding property of glyceollin I to the mammalian adenylyl cyclase (hereafter mAC), a critical target enzyme for the down-regulation of skin melanogenesis, has not been fully explored. To clarify the action mechanism between glyceollin I and mAC, we first investigated the molecular docking property of glyceollin I to mAC and compared with that of SQ22,536, a well-known mAC inhibitor, to mAC. Glyceollin I showed superiority by forming three hydrogen bonds with Asp 1018, Trp 1020, and Asn 1025, which exist in the catalytic site of mAC. However, SQ22,536 formed only two hydrogen bonds with Asp 1018 and Asn 1025. Secondly, we confirmed that glyceollin I effectively inhibits the formation of forskolin-induced cAMP and the phosphorylation of PKA from a cell-based assay. Long term treatment with glyceollin I had little effect on the cell viability. The findings of the present study also suggest that glyceollin I may be extended to be used as an effective inhibitor of hyperpigmentation.