• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.139-150
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• 1999

The ozone concentrations measured at the National Air Monitoring Stations between 1990 and 1995 were reviewed to detect any anomalies in the measurements. By screening the cases, in which variation of the ozone concentration from the previous measured value is greater than 75ppb, 125 station-days were identified as the test cases for the anomaly test. Historical and parallel consistencies of the measured concentrations were examined by plotting data for each test case. The detected anomalies can be classified into four categories; single outliers, anomalous variations during the startup period, baseline rises, and fluctuations in th diurnal variations. Anomalies were detected in as many as 80 cases among 125 test cases. Because of these anomalies, the number of hours exceeding 100ppb in the areas other than the Greater Seoul Area(GSA) could decrease from 157 to 107. Further studies for developing the methodology for eliminating the abnormal monitoring data are warranted for the data from the National Air Monitoring Stations are official to the both inside and outside of the country.

• Korean Journal of Childcare and Education
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• v.12 no.3
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• pp.61-78
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• 2016

The current study examined the relations among teachers' beliefs, behavioral self-regulation and school readiness of preschoolers. The study sample included 229 preschoolers aged 3 to 5 attending child care centers located in Seoul and Gyeonggi area of Korea. Using Structural Equation Modeling, the paths from teachers' beliefs to children's school readiness via the mediation of their behavioral self-regulation were examined. Children's self-regulation was directly assessed using Head-to-Toe Tasks. The results showed that teachers' stronger beliefs in and responsibility for children's self-regulation and interpersonal skills significantly predicted greater behavioral self-regulation among children, which in turn, significantly influenced greater social skills and work-related skills. The contribution of teachers' beliefs and behavioral regulation to social skills and work-related skills was positive and stronger for boys.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1452-1458
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• 2004

An experiment was conducted to examine the effects of sex and market weight on performance, carcass characteristics and pork quality. A total of 224 crossbred pigs (initially 26.64 kg BW) were allotted in a $2{\times}4$ factorial arrangement in a randomized complete block (RCB) design. The variables were sex (gilts and barrows) and different market weights (100, 110, 120 and 130 kg). Average daily gain (ADG) and average daily feed intake (ADFI) were significantly higher (p<0.01) in barrows than gilts, ADFI and feed conversion ratio (FCR) increased as body weight increased (p<0.05). Gender differences were observed in carcass characteristics. Backfat thickness and drip loss were greater in barrows (p<0.01), while loin eye area (p<0.01), flavor score (p<0.05) and lean content (p<0.001) were higher in gilts. Carcass grade and water holding capacity were the highest in 110 kg market weight pigs. The 100 kg arket weight pigs showed lower juiciness, tenderness, shear forces and total palatability than the other market weights (p<0.01). Hunter values (L*, a* and b*) were increased as market weight increased (p<0.05). Hunter a* value was greater in gilts (p<0.01) but L* value and b* value were not affected by sex of pigs. Net profit [(carcass weight${\times}$price by carcass grade)-(total feed cost+cost of purchased pig)] was higher in gilts than barrows (p<0.01), and was higher (p<0.05) in the pigs marketed at 110 and 120 kg market weight compared with 100 kg market weight. These results demonstrated that gilts showed higher carcass characteristics, pork quality, feed cost per kg body weight gain and net profit compared with barrows. Moreover, 110 or 120 kg body weight would be the recommended market weight based on pork quality and net profit for swine producers.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.449-458
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• 2000

Objectives : To determine the prevalence of prostatitis symptoms in the general population by questionnaire survey and to measure the effect of prostatitis symptoms on quality of life(QOL). Materials & Methods : A cross sectional community-based epidemiologic study was performed on 2,034 men, living in the Seoul metropolitan area using stepwise random sampling. Out of 2,034 interviewees, 1,356 men who were older than 40 and provided sufficient information were selected for this study. The questionnaires were completed by well trained interviewers. Contents of the questionnaires included demographic data, the Prostatitis Symptom Index(PSI), the International Prostate Symptom Score(IPSS), a general health questionnaire section and a sexual health questionnaire section. The PSI was composed of a sum of the scores from three questions about dysuria, penile pain and perineal pain and it ranged 0 to 12. Incidence of prostatitis symptoms was defined by a score of 4 or more and the reference group was defined as consisting of those with a score of 3 or less. The rate of incidence of prostatitis symptoms was assessed according to age and the difference of QOL between the prostatitis symptoms group and the reference group. Results : The overall positive rate of prostatitis symptoms measured by the PSI, in men older than 40, living in the Seoul metropolitan area, was 4.5%(61/1,356), adjusted to 4.8% by the relative proportion of this age group in the general population of the Seoul metropolitan area as compared to Korea and the World. The proportion of the group with prostatitis symptoms assessed by the PSI did not increase with age although the proportion of participants with moderate to severe lower urinary tract symptoms (LUTS) did increase with age. The group with prostatitis symptoms suffered from a much greater incidence of LUTS compared to the reference group (p<0.05). The QOL scores of the IPSS, and the general health and sexual health status of the group with prostatitis symptoms, were worse than those of the reference group.(p<0.05). Conclusions : The positive rate of prostatitis symptoms in men older than 40, living in the Seoul metropolitan area, was 4.8% and it didn't increase with age. The general QOL of the group with prostatitis symptoms was much worse than that of the reference group.

• Journal of Environmental Science International
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• v.20 no.12
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• pp.1585-1598
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• 2011

Emission reduction program for in-use diesel vehicles (ERPDV) has been enacted since 2004 over the Seoul metropolitan area, and diesel emission reduction is forced to fulfill this regulation. This study was performed to evaluate the ERPDV using $PM_{10}$ concentrations of both road-side monitoring and national background network during the period of 2004-2010. In order to assess the pure road emission, we first eliminated the long range transport effect by deducting the trend of annual national background concentrations from the road-side $PM_{10}$ concentrations, and then analyzed the time series of the resultant $PM_{10}$ concentrations over Seoul metropolitan area. The annual rates of variations of road-side $PM_{10}$ with the deduction of trend of background level show -3.2, +0.4, and -2.4 ${\mu}g/m^3$/year, in Seoul, Incheon, and Gyonggi province, respectively. There are steadily decreasing trend in Seoul with all of statistic parameters such as mean, mediam, 5%ile, 10%ile, 25%ile, 75%ile, 90%ile, and 95%ile concentrations. Incheon shows some fluctuations with positive with no significant trend, and Gyonggi province shows overall decreasing but not consistent. Student-t test shows 95% significant level of ERPDV effect in Seoul, but there exists no significant level greater than 90% in both Incheon, and Kyonggi province. Total annual averaged trend over the whole Seoul metropolitan area is estimated to lie in approximately $-2.9{\mu}g/m^3$/year in this study, implying the intimate involvement of ERPDV to a large extent. This is also suggesting that the further research cost-effectiveness of ERPDV with consideration of the long range transport process would be needed over the Seoul metropolitan area.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.2
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• pp.63-74
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• 2019

The objective of this study was to evaluate the influence of rainfall observation network on daily dam inflow using artificial neural networks(ANNs). Chungju Dam and Soyangriver Dam were selected for the study watershed. Rainfall and dam inflow data were collected as input data for construction of ANNs models. Five ANNs models, represented by Model 1 (In watershed, point rainfall), Model 2 (All in the Thiessen network, point rainfall), Model 3 (Out of watershed in the Thiessen network, point rainfall), Model 1-T (In watershed, area mean rainfall), Model 2-T (All in the Thiessen network, area mean rainfall), were adopted to evaluate the influence of rainfall observation network. As a result of the study, the models that used all station in the Thiessen network performed better than the models that used station only in the watershed or out of the watershed. The models that used point rainfall data performed better than the models that used area mean rainfall. Model 2 achieved the highest level of performance. The model performance for the ANNs model 2 in Chungju dam resulted in the $R^2$ value of 0.94, NSE of 0.94 $NSE_{ln}$ of 0.88 and PBIAS of -0.04 respectively. The model-2 predictions of Soyangriver Dam with the $R^2$ and NSE values greater than 0.94 were reasonably well agreed with the observations. The results of this study are expected to be used as a reference for rainfall data utilization in forecasting dam inflow using artificial neural networks.

• Journal of Environmental Policy
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• v.4 no.1
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• pp.1-19
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• 2005

On January 1, 2005, the Special Act on Metropolitan Air Quality Improvement, known as the Blue Sky 21 Program, entered into force. This Special Act is aimed at reducing the annual average concentrations of $PM_{10}$ and $NO_2$ to $40{\mu}g/m^3$ and 22ppb, respectively, from their current levels of $76{\mu}g/m^3$ and 36ppb, within the next 10 years. While the main focus of the Act is to reduce $PM_{10}$ and $NO_2$ emissions, the government also anticipates that these reductions would lessen high ozone occurrences and improve visibility. However, reducing local PM emissions would not decrease $PM_{10}$ concentrations as much as expected since other significant sources, such as continental inflow and/or secondary formation from photochemical reactions, exist. This is corroborated by the fact that $PM_{10}$ in the greater Seoul Metropolitan area during the ozone season is mostly in the form of $PM_{2.5}$, which is secondarily formed on a regional scale. Furthermore, many modeling results indicate so-called '$NO_x$ disbenefits,' referring to the fostering of an increase in ozone concentrations from a decrease in $NO_x$ emissions, over an extensive area. In this paper, the current status of air quality in the Seoul Metropolitan area is reviewed, and several other issues, including the effect of long-range transport, photochemical characteristics, and tasks for successful implementation of the Special Act are discussed.

• Korean Journal of Human Ecology
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• v.16 no.2
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• pp.315-331
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• 2007

The purpose of this study is to examine current situations about and factors related to expenditures of private education among pre-school children and to provide policy implications useful for future pre-school children education. The subjects of the study were parents of pre-school children under seven years of age, who lived in Seoul and Incheon area. The survey was conducted using parent questionnaire. The major findings of the study are: First, 86.8% of parents of pre-school children use private education and the average expenditure on it was 154, 446 won. Second, major factors determining their private education expenditure are educational level of parents, parents' job characteristics, household income, and region. Third, the most important reason for using private education among parents is to improve and excel in academic performance of their children. Forth, the higher the parents' expected returns from private education are, the higher the expenditure level of private education is. Fitth, the results of the logistic regressions showed that parents' attitudes toward private education was the most important factor in determining household economic burden associated with private education. The odds were 5 times greater for the parent group with strong desire for private education than for the parent group without it and 1.2 times greater for the parent group with high-expected returns from private education than the parent group without it. In conclusion, systematic, universal educational policies need to be developed to provide and support all the parents with pre-school children, given that their current economic burden is substantial. By providing such support, we can help parents focus on public education. This study examining current situations about and determining factors related to private education expenditures among pre-school children collected data limiting only Seoul and Inchoen area, therefore, future studies need to include data collected nationwide for generalizability of the findings. As well, development of more elaborated survey instruments and analytical methods would advance our understanding in the field.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.357-365
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• 2005

The typical patterns of surface $O_3$ pollution and their dependence on meteorology were studied in the Greater Seoul Area (GSA) during warm season (April-September) from 1998 to 2002. In order to classify the $O_3$ pollution patterns, two-stage (average linkage then k-means) clustering technique was employed based on daily maximum $O_3$ concentrations obtained from 53 monitoring sites during high $O_3$ events (118 days). The clustering technique identified four statistically distinct $O_3$ pollution patterns representing the different horizontal distributions and levels of $O_3$ in GSA. The prevailed pattern (93 days, $49.5\%$) distinctly showed the gradient of $49.5\%$ concentrations going from west to east in GSA. Very high $49.5\%$ concentrations throughout GSA (24 days, $12.8\%$) were also found as a significant pattern of severe $O_3$ pollution. In order to understand the characteristics of $O_3$ pollution patterns, the relationship between $O_3$ pollution patterns and meteorological conditions were analyzed using both synoptic charts and surface/upper air data. Each pattern was closely associated with surface wind interacted with synoptic background flow allowing to transport and accumulate $O_3$ and its precursor. In particular, the timing and inland penetration of sea-breeze were apparently found to play very important role in determining $O_3$ distributions.

• The Journal of the Petrological Society of Korea
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• v.16 no.4
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• pp.208-216
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• 2007

Based on digital geologic and geomorphic maps of 1 : 250,000 scale, distributive ratios of rock types were obtained by ArcGIS 9.0 program in the Gyeonggi, Seoul and Incheon areas of the Gyeonggi province. In the Gyeonggi area, 37 rock types are developed, and their geologic ages can be classified into Precambrian, Age-unknown, Triassic, Jurassic, Cretaceous and Quatemary. Among them, distributive ratios are decreasing in the order of Jurassic Daebo granites, Precambrian banded gneiss of Gyeonggi gneiss complex and Quatemary alluvium, all of which comprise about 83.7% of the rock types in the area. In the Seoul and Incheon areas, 10 and 15 rock types are developed, respectively., with the firmer being classified into Precambrian, Jurassic and Quatemary, and the latter into Precambrian, Jurassic, Cretaceous and Quatemary. In the Seoul area, distributive ratios are decreasing in the order of banded gneiss of Gyeonggi gneiss complex, Daebo granites and alluvium, which consist of 95.5% of the rocks in the area. In the Incheon area, distributive ratios are decreasing in the order of alluvium, Daebo granites, banded gneiss of Gyeonggi gneiss complex, reclaimed land, and schists of Gyeonggi gneiss complex, which occupy about 96.2% of the rocks in the area. The ratio of alluvium in the Incheon area is greater than that of Gyeonggi and Seoul areas, and the ratio of reclaimed land in the Incheon area is greater that of the Seoul, which can be attributed to the recent reclamation of the land for the industrial results such as new town development along the coastline of the Gyeonggi Bay.