• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.19-26
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• 2006

This study was undertaken to determine the concentrations of 15 aldehydes in air samples collected from 21 households including 9 atopy patient's homes and to assess the extent of exposure and risk for an individual due to inhalation. Of all the aldehydes identified in both indoor and outdoor environment, formaldehyde and acetaldehyde were the most abundant aldehydes, which were occupied $60\%\;and\;17\%$ of total amount, respectively. The geometric mean concentration of formaldehyde and acetaldehyde in indoor air were $170.5\pm1.9\;{\mu}g/m^3\;and\;47.3\pm1.5\;{\mu}g/m^3$, respectively. There existed a strong correlation between formaldehyde, acetaldehyde and other aldehydes. And the ratio of indoor and outdoor concentrations (I/O) exceeded 1.0 for almost every measured aldehydes except m-tolualdehyde... No associations were found between the level of aldehydes and either housing characteristics or living habits in most of the samples with only a few exception. And the concentrations of all aldehydes indoor air between atopy patient's homes and control homes were not significant(p>0.05). Formaldehyde and acetaldehyde exposures and risks were estimated by using the inhalation unit risk, mean concentrations and the 95th percentiles, and which were $2.6\times10^{-3}\;and\;1.1\times10^{-4}$, respectively. The mean and the 95th percentile risk estimates were 25 times higher for formaldehyde than for acetaldehyde in homes.

• Journal of Nutrition and Health
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• v.35 no.1
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• pp.69-77
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• 2002

The purpose of this study was to determine the probability of overweight throughout childhood in relation to the presence of overweight at birch or in early childhood, and presence of overweight in children's parents. Weight and height measures were collected at birth and at ages of 7, 10, 12 years from 655 6th grade primary schoolchildren. Childhood overweight was defined as a body mass index at or above the 85th percentile for age and sex, and overweight in children's parents as a body mass index at or above 27. The prevalence of overweight increased with age of the children. Overweight at birth was not associated with overweight at 12 years of ages. However, overweight at 12 years old was already related to overweight at 7 years old. In comparison to non-overweight peers, overweight children at ages 7(OR = 7.64, 95% CI = 4.32-13.51) and 10 years(OR = 19.69, 95% CI = 11.42-33.94) had a higher rick of becoming overweight at 12 years of age. Among children who was overweight at age 7years, 60.7% remained overweight 5 years later, Yearly increment in BMI of overweight children was larger than that of non-obese children (1.15-1.65kg/m$^2$vs 0.50-0.71kg/m$^2$. As compared with the lower case in mealy increment of BMI, the probability of being overweight at age of 12 years was greater in higher case. BMI values at age 7years were positively correlated with BMI values at age of 10 and 127ear,i, and with annual increments in BMI. But those relationships with birth weight were not observed. Children were at greater risk for overweight if at least ogle parent was overweight. The odds ratio for child overweight associated with maternal overweight was 2.41(95% CI = 1,13-5.IS), and those associated with paternal overweight 1.70(95% CI = 0.92-3.17). And parents' BMIs were positively correlated with children's BMI values and yearly BMI increment. In conclusion, overweight at early childhood and annual inclement in BMI can be important in predicting the prevalence of overweight and the risk that overweight will remain after 7 years of age. The risk of being overweight throughout the childhood increases by the parents'overweight.

• Journal of Preventive Medicine and Public Health
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• v.39 no.3
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• pp.235-242
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• 2006

Objectives: We wanted to determine the distribution of the clustering of the metabolic risk factors and we wanted to evaluate the related factors in young schoolchildren. Methods: A cross-sectional study of metabolic syndrome was conducted in an elementary school in Seoul, Korea. We evaluated fasting glucose, triglyceride, HDL cholesterol, blood pressures and the body mass index, and we used parent-reported questionnaires to assess the potential risk factors in 261 children (136 boys, 125 girls). We defined the metabolic risk factors as obesity or at risk for obesity ($\geqq$ 85th percentile for age and gender), a systolic or diastolic blood pressure at $\geqq90th$ percentile for age and gender, fasting glucose at $\geqq110mg/dl$, triglyceride at $\geqq110mg/dl$ and HDL cholesterol at $\leqq40mg/dl$. Results: There were 15.7% of the subjects who showed clustering of two or more metabolic risk factors, 2.3% of the subjects who showed clustering for three or more risk factors, and 0.8% of the subjects who showed clustering for four or more risk factors. A multivariate analysis revealed that a father smoking more than 20 cigarettes per day, a mother with a body mass index of = $25kg/m^2$, and the child eating precooked or frozen food more than once per day were associated with clustering of two or more components, with the odds ratios of 3.61 (95% CI=1.24-10.48), 5.50 (95% CI=1.39-21.73) and 8.04 (95% CI=1.67-38.81), respectively. Conclusions: This study shows that clustering of the metabolic risk factors is present in young schoolchildren in Korea, with the clustering being associated with parental smoking and obesity as well as the child's eating behavior. These results suggest that evaluation of metabolic risk factors and intervention for lifestyle factors may be needed in both young Korean children and their parents.

• 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.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.57-66
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• 2006

This paper presents new pedestrian signal timings considering pedestrian demand Pedestrian characteristics, and land use which were obtained by Pedestrian characteristics field survey and pedestrian signal operation survey. Pedestrian signal timings suggested were compared to the existing pedestrian signal timings by using real field data. pedestrian characteristics field survey was conducted to collect pedestrian crossing speed data and reaction time data. Sixteen areas in Seoul were selected for the data collection. The average pedestrian crossing speed was 1.30m/sec and the 15th Percentile speed was 1.11m/sec. The average reaction time was 2.24 seconds. Pedestrian crossing speed differs by land use, road width. pedestrian age, sex, and number of Pedestrians. Reaction time also differs by road width, pedestrian age, and number of pedestrians. Statistical testing was performed to secure reliability of the collected data.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.178-188
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• 2024

The dynamics of suspended sediment (SS) in forested catchments vary depending upon human or natural disturbances, including land use change, forestry activity, forest fires, and landslides. Understanding the dynamics of SS originating from the potential sources within a forested catchment is crucial for establishing an effective water quality management strategy. Therefore, to suggest a systematic method for interpreting SS dynamics, we evaluated the performance and applicability of ten methods for calculating the hysteresis index based on observed hydrological data and two calculation models (Lawler's method and Lloyd's method) with five sampling intervals (50th, 25th, 10th, 5th, and 1st percentiles). Our results showed that Lloyd's method, which used a sampling interval at the 1st percentile, had the largest number of analyzable runoff events and exhibited the best performance. The results of this study can contribute to quantifying the hysteresis in the relationship between discharge and SS and provide useful information for interpreting SS dynamics.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.768-772
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• 2006

To assess the dietary exposure to 3-monochloropropane-1,2-diol (3-MCPD) from soy sauces, the levels of 3-MCPD in commercial soy sauces were analyzed with gas chromatography/mass spectrometry. Sixty nine out of the 72 soy sauces tested contained a level of 3-MCPD below $0.3\;{\mu}g/g$, the maximum limit in Korea. The average concentration of the 72 samples was $0.080\;{\mu}g/g$ and the highest concentration was $3.131\;{\mu}g/g$. On the basis of the consumption data, 3-MCPD concentration and body weight, the estimated daily exposures to 3-MCPD were ranged from 0.037 to $0.146\;{\mu}g/kg$ body weight (bw)/day for 95th percentile exposed population groups. Our estimated daily exposures are significantly lower than the provisional maximum tolerable daily intake (PMTDI) of $2\;{\mu}g/kg$ bw/day, which was established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA).

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.4
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• pp.10-15
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• 2012

The design of automobile occupant seat belt system has been studied by using MADYMO. Based on the FMVSS 208 (Federal Motor Vehicle Safety Standards 208) and the USNCAP (United States New Car Assessment Program) regulations, seat belt design parameters were chosen for the design improvement to the 5th percentile female dummy: limit force of load limiter, time to fire of shoulder belt, inlet length of shoulder belt, inlet length of lap belt. The design of experiment method was employed to optimize the design parameters of passenger seat belt. Range of injury probability due to the change of H-point position was estimated by the simulation.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.611-619
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• 2003

Characteristics of the ozone concentrations in Seoul were analyzed for the data between May and September from 1996 to 2000. Observation data from 27 stations in Seoul are used. Among the results from 27 stations, representative results from 2 stations (City hall and Gwanak representing downtown and background areas of Seoul, respectively) are presented. The 24-hour average ozone concentrations of Gwanak (28.6 ppb) are higher than City hall (14.9 ppb). The 24-hour average ozone concentrations on Sunday are higher than other days at both sites. During weekday, the 24-hour average ozone concentrations on Wednesday are higher than other days. Although the mean of the I-hour daily maximum ozone concentrations at Gwanak is higher than City hall, the . ozone concentrations above 95th percentile at City hall are higher than Gwanak. As a result, the number of days on which the 1 - hour ozone concentration exceeding 100 ppb and 120 ppb at Gwanak (17 and 3) are lower than City hall (29 and 9). To sum up, both sites are VOCs limited region and the mean ozone concentration in Gwanak is higher because of the lower N0$_2$ concentration. But high ozone cases occur more frequently in City hall when conditions are right.

• Nutrition Research and Practice
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• v.4 no.1
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• pp.82-88
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• 2010

This study aimed to define a one portion size of food items frequently consumed for convenient use by Koreans in food selection, diet planning, and nutritional evaluation. We analyzed using the original data on 5,436 persons (60.87%) aged 20~64 years among 8,930 persons to whom NHANES 2005 and selected food items consumed by the intake frequency of 30 or higher among the 500 most frequently consumed food items. A total of 374 varieties of food items of regular use were selected. And the portion size of food items was set on the basis of the median (50th percentile) of the portion size for a single intake by a single person was analyzed. In cereals, the portion size of well polished rice was 80 g. In meats, the portion size of Korean beef cattle was 25 g. Among vegetable items, the portion size of Baechukimchi was 40 g. The portion size of the food items of regular use set in this study will be conveniently and effectively used by general consumers in selecting food items for a nutritionally balanced diet. In addition, these will be used as the basic data in setting the serving size in meal planning.