• Analytical Science and Technology
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• v.19 no.1
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• pp.73-85
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• 2006

Blood serum concentrations of polychlorinated biphenyls (PCBs) were measured in employees who worked at a municipal solid waste incinerator (MSWI), members of residential community who lived near the MSWI (<0.3km) and members of residential community lived far from the MSWI (>10 km). Human blood serum samples were analyzed for all PCB congeners using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). The mean levels of total PCBs and dioxin-like PCBs in 87 serum samples were 242.77 ng/g lipid and 8.83 TEQ pg/g lipid, respectively. The PCB homologue profiles showed that penta-, hexa-, hepta-chlorinated biphenyls contributed more than 80% of the total PCBs concentration. The most abundant congeners were PCB153, PCB138, PCB180, PCB187, PCB118. A statistical analysis was performed to determine whether there were significant correlations between PCB concentrations and specific variables such as age, gender, smoking habits, occupation, BMI (Body Mass Index) and time of residence. As a result, the age was found to be strongly correlated with serum PCB concentrations. In addition, there were strong correlations between total PCBs and PCB153 (r=0.93, p<.0001), dioxin-like PCBs and PCB118 (r=0.98, p<.0001). So these two congeners are satisfactory indicators for total PCB concentrations and dioxin-like PCBs in human blood respectively.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.155-163
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• 1998

The purpose of this study was to determine the association between blood lipids, fibrinogen, fasting blood sugar, lifestyle-related factors and lipoprotein(a). This study was performed with 140 healthy adults (male:80, female:60) among the teachers in primary, middle, and high school in Seoul in November 1996. Lipoprotein(a) concentration was measured with an enzyme-linked-immunosorbents assay(ELISA), and the results showed that the distribution was highly skewed and the average concentrations of male and female were $16.94{\pm}12.70\;mg/dL\;and\;17.92{\pm}7.58\;mg/dL$, respectively. The percentage of subject with lipoprotein(a) concentrations higher than 30 mg/dL was 26.4%. Univariate analysis showed significant association between lipoprotein(a) and age, alcohol, meat, and NaCl consumption (p<0.05). In multivariate analysis, lipoprotein(a) correlated positively with age (p<0.05) and meat consumption (p<0.01). These data suggest that lifestyle-related factors may affect the lipoprotein(a) concentration regarded as a risk factor of atherosclerosis disease.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.423-433
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• 2018

Particulate matter air pollution is a serious problem affecting human health and visibility. The variations in $PM_{10}$ concentrations are influenced by not only local emission sources, but also atmospheric circulation conditions. In this study, we investigate the temporal features of $PM_{10}$ concentrations in South Korea and the atmospheric circulation patterns associated with high concentration episodes of $PM_{10}$ during winter (December-January-February) 2001-2016. Based on those analyses, a Korea Particulate matter Index (KPI) is developed to represent the large-scale atmospheric pattern associated with high concentration episodes of $PM_{10}$. The atmospheric patterns are characterized by persistent high-pressure anomalies, weakened lower-level north-westerly anomalies, and northward shift of the upper-level meridional wind anomalies near the Korean Peninsula. To evaluate the change in occurrence of high concentration episodes of $PM_{10}$ under a possible future warmer climate, we apply KPI analysis to CMIP5 climate simulations. Here, historical and two representative concentration pathway (RCP) scenarios (RCP 4.5 and RCP 8.5) are used. It is found that the occurrence of atmospheric conditions favorable for high $PM_{10}$ concentration episodes tends to increase over South Korea in response to climate change. This suggests that large-scale atmospheric circulation changes under future warmer climate can contribute to increasing high $PM_{10}$ concentration episodes in South Korea.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.346-347
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• 2001

Sampling bag은 비교적 저렴한 가격으로 쉽게 구할 수 있어 VOC 및 악취물질을 분석할 때 널리 사용되고 있다. 그러나 저농도의 분석에서는 흡착으로 인한 농도 변화가 일어날 수 있어 분석결과에 큰 영향을 줄 수 있다고 알려져 있다. 그러나, bag내부에서의 안정도에 대한 충분한 조사가 이루어져 있지 않아 VOC 화합물이 얼마나 bag에서 안정성의 문제가 있는지에 대한 정량적인 이해가 매우 부족한 실정이다. (중략)

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.125-126
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• 2014

습식도금에 사용되는 처리액의 성분농도는 다양한 요인 때문에 변화한다. 안정한 품질로서 처리하기 위하여 성분이나 반응생성물 농도를 분석하고 처리액 농도를 파악하여 유지 관리할 필요가 있다. 도금약품개발에 즈음하여 약품제조사는 가동범위가 넓고 불순물 혼입에 강한 조성개발을 시도했다. 본고에서는 표면처리에 사용되는 전처리용액, 도금액 분석에 사용되는 방법, 조성과 관리에 관하 여 기술하였다.

• Journal of the Korean earth science society
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• v.23 no.3
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• pp.280-293
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• 2002

In this study, we analyzed the long-term distribution patterns of $CH_4$ determined from the Moo-Ahn (MAN) observatory in relation with those derived from the world major background monitoring sites. Comparison of the data were made using those data sets collected for the period between Aug. 1995 to Dec. 1991. The mean $CH_4$ concentration of MAN observatory was measured to be 1898${\pm}$85.3 ppb, recording the highest concentration of all the monitoring sites. When the concentration of $CH_4$ for different stations was compared over latitudinal scale, its concentration appeared to increase systematically as a function of latitude with an exception of MAN (and the other Korean monitoring site at Tae Ahn). Moreover, such phenomenon was more distinctive in Northern than Southern Hemisphere. According to the analysis of the monthly distribution patterns of $CH_4$ at MAN observatory, its concentration level began to increase from the months of February/March and peaked during August. In addition, when the level of oscillation in monthly concentrations (between the maximum and minimum values) was checked, differences were significant between MAN and other monitoring stations. If the rate of concentration change was checked using the data sets collected for this limited time period in terms of linear regression analysis, results for MAN showed the highest annual increasing rate of 16.5 ppb. It is hence suggested that the largest variability in the $CH_4$ distribution patterns at MAN observatory may be reflected by the high irregularity in its source/sink processes.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.651-658
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• 1998

최근 원자력발전소주변 환경방사선에 대한 국민적 관심이 고조되고 있으나 환경중 방사능 축적에 대한 허용기준치가 정립되어 있지 않아 효과적인 대 국민 홍보에 한계가 있다. 따라서 원전 주변 주민의 생활습관을 파악하여 섭취량을 품종별로 분류하여, 조사, 분석함으로서 환경시료중 방사능 허용농도를 설정함으로서 원자력발전소 주변 환경방사능 농도를 설정된 허용농도와 비교하여 원전의 안전성에 대한 대 국민 이해 및 신뢰 회복에 이바지 하고자 한다. 또한 최대허용농도를 기준으로 삼던 기존의 방식이 퇴색하고 ALI［l］를 이용한 국내 실정에 맞는 식품 중 허용농도 설정의 필요성이 대두되고 있는 현 실정을 감안하여 ALI를 이용하여 식품 중 최대허용농도를 설정하고자 한다.

• Analytical Science and Technology
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• v.12 no.1
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• pp.75-79
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• 1999

The concentration of polyamine and the relationship between the concentration of PA and cold resistance were analysed during the cold stress in the cotyledons and hypocotyls of young spring radishes. The concentration of PUT was increased during the cold stress in the cotyledons and the concentration of PUT and SPD was changed significantly all the stress time. From the results, we suggested that PUT and SPD were synthesized against cold stress or separated from the bound PA during the cold stress. But, the concentration of SPM was not significantly changed during the cold stress. Only SPD existed in the control hypocotyls. The concentration of SPD was increased during the cold stress, but was decreased dramatically during continusly cold stress. The reactivity against stress of hypocotyls was generally more sensitive during the cold treatment than that of the cotyledons because of the lower concentration of PA in the hypocotyls. PUT and SPD were responsible for the resistance of cold stress in the cotyledons and PA did not play an important role on the resistance of cold stress in the hypocotyls. In this study we suggest that PUT and SPD were responsible for the increase of the resistance against the cold stress.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.452-452
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• 2021

하천 및 호소수역에 대한 수질오염원이 지속적으로 증가하는 경우에는 일반적인 농도규제 방식으로는 수질개선에 한계가 나타난다. 이를 해결하기 위해 목표 수질 한도 내에서 유역 배출원의 오염물질총량 관리를 목적으로 하는 수질오염총량관리제 개념이 도입되어 단위유역 지자체별 배출부하량을 관리하고 있지만, 지역의 오염원 배출 특성을 고려하지 않은 저감계획은 오히려 유역 내 새로운 오염원으로 전락하여 수질 개선 효과가 나타나지 않을 수 있다. 따라서 효율적인 총량 관리를 위해서는 수계 내 오염원 파악이 필수적이다. 본 연구에서는 수질오염총량제 대상 하천인 굴포천의 수질 오염원 분석을 위해 2016년, 2017년 굴포천 유역 토지이용 자료를 활용하여 수질항목과의 상관성을 파악하고 2016년부터 2020년까지 최근 5년 동안 총량측정망을 통해 측정된 유량 및 수질 자료를 이용해 상류, 중류, 하류 각각의 유량-부하량 관계식을 도출하여 지점별 수질 오염원 특성을 분석하였다. 상관분석 결과, 강우 시 밭과 BOD, SS, T-P는 양의 상관성을 보였고, T-N은 강우, 비 강우 시 관계없이 밭, 논에서 높은 양의 상관성을 보였다. 유량-부하량 관계식 도출 결과, 상류의 경우 BOD, COD, T-P, TOC, SS는 유량이 증가함에 따라 농도가 감소하는 특성을 나타내었는데 이는 2019년 4월 이후 오존처리 재이용수 방류에 따른 유량 증가의 영향이라고 사료 된다. 반면 T-N은 유량이 증가함에 따라 농도가 증가하는 특성을 나타내었는데 이는 오존처리 재이용수의 T-N 농도가 하천의 T-N 농도 보다 높아 발생한 것으로 보인다. 중류와 하류의 경우 BOD, COD, T-P, TOC, SS는 유량이 증가함에 따라 농도가 증가하는 특성을 나타내어 강우 시 비점오염원의 영향이 있는 것으로 보인다. 특히, 하류의 경우 유량이 증가함에 따라 수질 농도가 급격히 증가하여 중류에 비해 비점오염원 영향이 더 큰 것으로 나타났다.

• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.413-421
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• 2011

The present study was carried out to summarize the effect of garlic in the hyperlipidemia rats by meta-analysis related studies. The association measure to test effect of garlic was the mean difference (MD). In this particular fixed-effect model of mean difference, body weight, liver weight, kidney weight and heart weight were significantly decreased (p < 0.05). Also, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. In this case of heterogeneous variable, random effect model was applied. In this model, liver weight, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. According to the meta-regression analysis, duration of injection was significantly for kidney weight, testis weight, plasma total cholesterol, plasma triglycerides, HDL-cholesterol, LDLcholesterol, liver cholesterol, liver triglycerides.