• Journal of Environmental Health Sciences
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• v.40 no.4
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• pp.279-293
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• 2014

Objectives: Children are more susceptible to heavy metal toxicity than adults. The purpose of this study was to evaluate heavy metal concentrations in the blood of Korean preschoolers and investigate the association between metals in blood and related factors. Methods: A total of 512 subjects from 36 to 83 months of age were sampled. A questionnaire survey was performed and the levels of lead, mercury and cadmium were measured in the blood samples of all subjects. Their parents were interviewed in order to obtain information on basic characteristics, dietary patterns, socio-economic factors, and indoor/outdoor environment of the preschoolers. Multiple linear regression was used to analyze the association between the above factors and lead, mercury or cadmium concentrations. Results: The geometric mean concentrations of lead, mercury and cadmium in the blood were $1.45{\pm}1.58{\mu}g/dL$, $2.14{\pm}1.74{\mu}g/dL$ and $0.23{\pm}1.91{\mu}g/dL$, respectively. Results from multiple linear regression analysis showed that blood lead levels were associated with birth weight and paternal smoking status. Daily mercury intake from food and maternal education were also shown to influence mercury concentrations in blood. Also, blood cadmium concentrations were associated with maternal age and having a bus garage near the place of residence. Conclusion: This study suggests that smoking status, dietary patterns and the environmental status near the residence should be considered as important factors for preventable sources of heavy metal exposure in preschoolers.

• Journal of Preventive Medicine and Public Health
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• v.41 no.1
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• pp.61-67
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• 2008

Objectives : Polycyclic aromatic hydrocarbons (PAH) and toluene have been reported to induce reactive oxygen species and oxidative stress. This study was performed to investigate the effects of low level exposure to PAHs or toluene on the lipid peroxidation level in elementary school children and the elderly in a rural area. Methods : Forty seven elementary school children and 40 elderly people who were living in a rural area and not occupationally exposed to PAH or toluene were the subjects of this study. Information about active or passive smoking and diet was obtained using a self-administered questionnaire. The urinary 1-hydroxypyrene (1-OHP), 2-naphthol, hippuric acid and thiobarbituric acid reactive substance (TBARS) concentrations were measured, and these values were corrected with the urinary creatinine concentration. Results : In school children, the geometric means of the urinary 1-OHP, 2-naphthol, hippuric acid and TBARS levels were $0.02\;{\mu}mol/mol$ creatinine, $0.47\;{\mu}mol/mol$ creatinine, 0.14 g/g creatinine and $0.95\;{\mu}mol/g$ creatinine, respectively. Those values for the elderly were $0.07{\mu}mol/mol$ creatinine, $1.87{\mu}mol/mol$ creatinine, 0.11 g/g creatinine and $1.18\;{\mu}mol/g$ creatinine, respectively. The mean levels of urinary 1-OHP, 2-naphthol and TBARS were significantly higher in the elderly subjects than in the children. The urinary TBARS level was not correlated with the urinary 1-OHP, 2-naphthol and hippuric acid, but they were correlated with the age of the subjects. Conclusions : These results suggest that low level inhalation exposure to PAH or toluene does not markedly increase lipid peroxidation, and age is a significant determinant of lipid peroxidation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.2
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• pp.29-38
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• 2012

The data quality and measurements along consecutive detector stations can vary much even in the same traffic conditions due to variety in detector types, calibration and maintenance effort, field operation periods, minor geometric changes of roads and so on. These faulty situations often create 10% or more of inherent difference in important traffic measurements between two stations even under stable low flow condition. Low detection rates(DR) and high false alarm rates(FAR) therefore sets in among many popular Automatic Incident Detection Algorithms(AIDA). This research is two-folded and aims mainly to develop a new AIDA for uninterrupted flow. For this purpose, a technique which utilizes a Simple Arithmetic Operation(SAO) of traffic variables is introduced. This SAO technique is designed to address the inherent discrepancy of detector data observed successive stations, and to overcome the degradation of AIDA performance. It was found that this new algorithm improves DR as much as 95 percent and above. And mean time to detection(MTTD) is found to be 1 minutes or less. When it comes to FAR, this new approach compared to existing AIDAs reduces FAR up to 31.0 percent. And capability in persistency check of on-going incidents was found excellent as well.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.168-179
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• 1994

In some ceramic industries, worker exposure to dust, crystalline free silica and lead were determined and evaluated. The conclusions are as follows. 1. Crystalline silica in bulk samples was 10.5 % in sanitary ware industry, 9.4 % in tile industry, and 2.1 % in ceramic insulator industry respectively. The free silica content of air filter sample was 8.03 % in table ware industry, 5.59 % in sanitary ware industry, and 1.32 % in ceramic insulator industry. Because silica content in ceramic dust is relatively high, it is should be considered silica as important factor in evaluating for ceramic industry. 2. The silica contents in dust from tile, sanitary ware and table ware industries are above 5%, it should be classified as "Type" 2 dust. 3. The airborne concentration of respirable crystalline silica was $27.9{\mu}g/m^3$ in a sanitary ware factory and $5.8{\mu}g/m^3$ in a ceramic insualtor factory. Three of ten samples sampled the above factories were exceeded the occupational exposure levels, $100{\mu}g/m^3$. 4. Geometric mean(GM) of total dust in 11 factories was $1.00mg/m^3$ and GM of respirable dust concentration in 5 factories was $0.33mg/m^3$. Sanitary ware industry had the highest concentration of total dust, $1.62mg/m^3$ and of respirable dust, $0.88mg/m^3$. 5. Average lead concentration in air was $0.05mg/m^3$ in glazing process of 2 factories manufacturing table ware. Five of ten sample(50%) were exceeded $0.05mg/m^3$. Therefore lead exposure in pottery industry should be considered as important problem.

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.21-31
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• 2012

This paper presents the short-term and long-term measures to determine the fugitive dust concentration in a contaminated site, which is a crucial step for the determination of particulate emission factor (PEF) for risk assessment. As a long-term measure, USEPA method employing Q/C value (inverse of the ratio of the geometric mean air concentration to the emission flux at center of a 0.5-acre square source) seems to be suitable as it reflects regional-specific meteorological conditions. However, it requires nation-wide database collection and interpretation. Use of ASTM method is an alternative as a short-term measure. The method is readily field-applicable as PEF calculation equation is simple and input parameters can be easily derived at the site of interest as well without the nation-wide efforts. Using ASTM method, PEF at the Former Janghang Smelter Site was determined. According to various mode of aggregate size distribution and fractions of vegetative cover, which are the most important factors in PEF calculation, PEF values at the Former Janghang Smelter Site varied greatly. When the mode of aggregate size distribution was set at 0.25 mm, PEF values at the Former Janghang Smelter Site was 5~20 times higher than the default PEF value (i.e., 35 ${\mu}g/m^3$) shown in the current Korean Soil Contamination Risk Assessment Guidance. On contrast, when the mode was set at 2 mm, PEF values at the Former Janghang Smelter Site was 160~640 times lower than the default PEF value in the Korean Guidance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.3
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• pp.61-71
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• 1988

The stage-discharge relation curve(rating curve) is the basic formula in hydrologic analysis. It plays an important role in converting to the discharge from available flood water level data including the daily mean stage. However, the river induces a cross section change at the gauging station because of the composed material of the river bed and three processes of the stream flow; i.e., erosion, transportation, and sedimentation. Rating curve has to be revised according to the temporal variation of the river bed due to the those factors. In this study, the basic rating curve is developed with respect to the current river bed to convert the existing rating curves and also to seize the hydraulic and geometric characteristics for the temporal variation of the river bed, relationships among the basic rating curve and the existing rating curves, water level, cross sectional area, and flow velocity are analyzed. Indogyo station, which is not only the key station of the Han river but also greatly changed the river bed after completion of the Han river development plan during the year 1983 to 1986, was chosen for the study. In this study, the river bed is assumed in a dynamic equilibrium condition. The basic rating curve is developed using hydrologic data of the physical year of 1987. For a given discharge, relationships for conversion of previous data, stage and velocity, the current one are formulated. To verify the usefulness of the relationships, stage-cross sectional area and stage velocity formula are also derived. Both hydrologic method using continuity equation and statistical method by the rating curve are compared and checked, then the validation of the both are positively shown.

• Journal of Nutrition and Health
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• v.47 no.5
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• pp.364-373
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• 2014

Purpose: The purpose of this study was to develop a mercury database for food commonly consumed by Koreans. Methods: Target foods for a mercury database were selected from dietary survey data of the 2007-2009 Korean National Health and Nutrition Examination Survey (KNHANES). Data for mercury contents of foods were collected through literature review. Among 702 food items reported by 24 hr dietary recall method, the contents of mercury for 300 food items were selected with systematic evaluation from the literature, which provided analytical values, and those of 56 food items were imputed by using a conversion factor. Results: The mercury database developed in this study covered 50.7% of all kinds of consumed foods and 95.1% of total amount of food intake reported by 2007-2009 KNHANES. In the database, the geometric mean of mercury contents in food items was the highest in the fishes and shellfishes group ($41.13{\mu}g/kg$, n = 101) followed by mushrooms ($18.93{\mu}g/kg$, n = 12) and seaweeds ($5.92{\mu}g/kg$, n = 14), and the lowest in the meats group ($0.15{\mu}g/kg$, n = 17). Conclusion: The developed mercury database can be used to estimate the dietary mercury exposure of Korean people, and the method for development of a mercury database would be helpful to researchers in development of a new database for other food borne hazardous substances.

• Journal of the Korean Society of Costume
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• v.32
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• pp.163-182
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• 1997

The purpose of this study was intended to analyze artistic formativeness represented in the modern fashion design materials. Nowadays the modern fashion design materials is characterized by variety. The fashion materials the most important of fashion is called a softwear in textile industry and emerged as a new field. Fashion design also escaped from the tra-ditional restraint and extended to pursue lib-eral clothes and the designer's creative inten-tion has resulted in conceptual and conven-tional alteration as a new mode of plastic ex-preseeion. As a results of analysis of the formative fea-ture of Art style represented in the modern fashion design materials. First Surrealism had been searching for a new way of confronting a social and rtistic environment that was stifling and repugnant to them. Accordingly the wide applicaytion of the various object due to the thought of Sur-realism through the modern fashion materials brought the diversification and individua-lization of the modern fashion design. Second Pop Art that is made modern mech-anic culture and commercialism brought the great transformation in the history of Art out of the existing style and the sense of ex-pression. And the plastic characteristics of Pop Art that has a gravity as modern fashion materials on a them of the elements of popular consumer's society. That is the common and cheap objects were introduced into fashion materials itself or pat-tern. Third Minimalism is a trend in art att-empting to seek essence of the object by presenting simple and disciplined expressions by minimal formative means. The features of external form are simplicity clarity unrelated composition and symmetrical structure. Mini-malism was a quest for basic elements repre-senting the fundamental esthetic values of art. The minimal expression in modern fashion materials mean fabrics with simple surface and is contained using simple geometric pattern or utilizing textiles without any patterns. Fourth Eroticism is a kind of psychological revolution in the development of human civilization and is deeply rooted in the cultural tradition of myth religion customs and art. So Eroticism must be distinguished from a mere animal reproduction. These erotic char-acteristics were holded the meanings of sexu-ality through the modern fashion materials. Especially it was expressed the sexual part of body was nakedly showed through trans-parent materials or semitransparent like metalic and opaque materials. Recently the various kinds of new materials such as paper vinyle plastic metal as well as human body were applied to new fashion de-sign. First of all the new materials will give modern fashion designers stimuli and inspi-ration. It can also express values of moderners to despise materialism and uniformed modern society and to recover humanity and self-actualization.

• Journal of Korea Water Resources Association
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• v.46 no.1
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• pp.47-58
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• 2013

Recently, an increase in the occurrence of sudden local flooding of great volume and short duration due to global climate changes has occasioned the significant danger and loss of life and property in Korea as well as most parts of the world. Such a local flood that usually occurs as the result of intense rainfall over small regions rises quite quickly with little or no advance warning time to prevent flood damage. To prevent the local flood damage, it is important to quickly predict the flood severity for flood events exceeding a threshold discharge that may cause the flood damage for inland areas. The aim of this study is to develop the NFI (New Flood Index) measuring the severity of floods in small ungauged catchments for use in local flood predictions by the regression analysis between the NFI and rainfall patterns. Flood runoff hydrographs are generated from a rainfall-runoff model using the annual maximum rainfall series of long-term observations for the two study catchments. The flood events above a threshold assumed as the 2-year return period discharge are targeted to estimate the NFI obtained by the geometric mean of the three relative severity factors, such as the flood magnitude ratio, the rising curve gradient, and the flooding duration time. The regression results show that the 3-hour maximum rainfall depths have the highest relationships with the NFI. It is expected that the best-fit regression equation between the NFI and rainfall characteristics can provide the basic database of the preliminary information for predicting the local flood severity in small ungauged catchments.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.561-569
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• 2012

To evaluate the bacteriological water quality in Yongnam-Gwangdo, located in western Jinhae Bay, seawater samples were analyzed using sanitary indicator bacteria at 57 sampling stations. According to survey results from January 2007 to December 2009, the range of the geometric mean and the estimated 90th percentile for coliforms and fecal coliforms in the samples were <1.8-16.5 and 1.8-246.8 MPN/100 mL and <1.8-7.1 and 1.8-74.8 MPN/100 mL, respectively. The samples, including those taken from stations located in Wonmunman, Gwangdo, and Dangdong, showed high levels of microbial contamination caused by the climate and weather patterns in the marine environment. The bacteriological water quality in the area met Korean criteria for a designated shellfish growing area for export and National Shellfish Sanitation Program criteria for an approved shellfish growing area, except at station #49. A total of 24 direct pollution sources were discharged into the shellfish growing area. The radius of impact was calculated for each pollution source to assess the effect on the shellfish growing area. The calculated radius of impact for most of the pollution sources was below 300 m. However, the radius of impact for the combined pollution sources in Kyeonnaeryang was 93-1973 m. There were significant differences between the calculated closed sea area and actual monitoring results. The closed sea area values calculated from the fecal coliform load in drainage water tended to be higher than the actual monitoring results. Tidal currents and environmental factors such as salinity, water temperature, sunlight, and microbiological factors affect the survival of fecal indicator bacteria in seawater.