• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.38-45
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• 2017

Objectives: Radon may be second only to smoking as a cause of lung cancer. Radon is a colorless, tasteless radioactive gas that is formed via the radioactive decay of radium. Therefore, radon levels can build up based on the amount of radium contained in construction materials such as phospho-gypsum board or when ventilation rates are low. This study provides our findings from evaluation of radon gas at facilities and offices in an industrial complex. Methods: We evaluated the office rooms and processes of 12 manufacturing factories from May 14, 2014 to September 23, 2014. Short-term data were measured by using real-time monitoring detectors(Model 1030, Sun Nuclear Co., USA) indoors in the office buildings. The radon measurements were recorded at 30-minute intervals over approximately 48 hours. The limit of detection of this instrument is $3.7Bq/m^3$. Also, long-term data were measured by using ${\alpha}-track$ radon detectors(${\alpha}-track$, Rn-tech Co., Korea) in the office and factory buildings. Our detectors were exposed for over 90 days, resulting in a minimum detectable concentration of $7.4Bq/m^3$. Detectors were placed 150-220 cm above the floor. Results: Radon concentrations averaged $20.6{\pm}17.0Bq/m^3$($3.7-115.8Bq/m^3$) in the overall area. The monthly mean concentration of radon by building materials were in the order of gypsum>concrete>cement. Radon concentrations were measured using ${\alpha}-track$ in parallel with direct-reading radon detectors and the two metric methods for radon monitoring were compared. A t-test for the two sampling methods showed that there is no difference between the average radon concentrations(p<0.05). Most of the office buildings did not have central air-conditioning, but several rooms had window- or ceiling-mounted units. Employees could also open windows. The first, second and third floors were used mainly for office work. Conclusions: Radon levels measured during this assessment in the office rooms of buildings and processes in factories were well below the ICRP reference level of $1,000Bq/m^3$ for workplaces and also below the lower USEPA residential guideline of $148Bq/m^3$. The range of indoor annual effective dose due to radon exposure for workers working in the office and factory buildings was 0.01 to 1.45 mSv/yr. Construction materials such as phospho-gypsum board, concrete and cement were the main emission sources for workers' exposure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.737-744
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• 2016

Seoul Metropolitan Area has been changed by fierce internal migration during the last several decades. To determine the regional structure, we analyzed the in-and-out migration pattern and main factors affecting the intense of mobility. The migration within metropolitan city and province shows that in Seoul, Songpa and Dobong Gu gained a large population, in Incheon, Namdong Gu experienced a huge population influx, and in Gyeonggi Province, Hwasung, Yongin and Paju city gained a great population. In Seongnam, Suwon city lost a lot of population. These population gains and losses came from mainly residential redevelopment projects in the metropolitan city and new land development projects in Gyeonggi Province. The main factors affecting the intense of mobility diverse from city characters. In central type cities, house price gets the more population influx. In job-housing balanced cities, total income growth rate, housing supply rate and roads cause in-migration. In bed-town type cities, the increase of housing supply rate and parks increase the population. In suburban type cities, business density, housing supply rate, housing, subway station number and educational facilities increase population from outside the city. So, we have to prepare more detailed urban and housing policy responses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.275-284
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• 2017

As the 3D Greenery system is known to improve the urban environment, it works as new alternative for eco-friendly building and warrants further study for application to the domestic field. This study aimed to apply the design components for eco-friendly composition by investigating the spatial characteristics of the 3D Greenery System reflected in interior and exterior of buildings and to analyze the organization and design elements of domestic and foreign cases. The results showed that instances of the Greenery System tended to be a large scale and high-density development in order to expand various exterior spaces. Although its early forms were often found in such public facilities as exhibition and education purpose, cases of multi-unit dwelling have been growing. Allowing apartment residents to prefer intimate space by providing various such spaces for residential units and offering independent green spaces would induce diverse residents' lifestyles rather than monotonous design. The analysis also indicated that community space composed of various outdoor spaces and atmosphere would change life patterns of multi-housing and establish a real neighborhood through social interaction. Moreover, further investigation of the design patterns of outdoor space arrangement is needed since the Greenery system actively reflects the environmental characteristics of building sites and clearly shows a tendency to utilize natural terrain and slope in building shapes.

• Journal of the Korean Society of Child Welfare
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• no.54
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• pp.145-172
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• 2016

The purpose of this study was to examine whether parenting attitudes would have an effect on the developmental trajectories of school adjustment for adolescents in out-of-home care. Additionally, we hypothesized that this model would be different between boys and girls. In this study, we analyzed three waves of data collected from 341 adolescents living in residential facilities, group homes or foster homes by using cluster sampling methods. Growth-curve longitudinal analysis was conducted, and the results indicated that levels of school adjustment had increased from the 1st through the 3rd grade of middle school. Positive parenting attitudes had a positive impact on initial school adjustment and rate of change, whereas negative parenting attitudes had a negative impact only on the initial school adjustment. Second, multi-group analysis revealed that there were group differences between boys and girls in their initial school adjustment by positive parenting attitudes. Based on these results, this study discussed further suggestions to increase school adjustments for adolescents in out-of-home care.

• Journal of Environmental Health Sciences
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• v.45 no.2
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• pp.113-125
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• 2019

Objectives: Although the risk assessments for nitrogen dioxide ($NO_2$) and ozone ($O_3$) have been extensively studied, most of the existing risk assessments were limited mainly to indoor environments such as workplaces, schools, and multi-use facilities. Therefore, integrated risk assessment is needed to consider exposure in all microenvironments, including outdoors. The purpose of this study was to assess the differences in risk among sub-population groups according to time-activity patterns and reported concentrations, as well as the lifetime risk of Koreans. Methods: In this study, we estimated time-weighted average exposure concentrations of $NO_2$ and $O_3$ for preschool children, students, housewives, workers, and seniors using residential time and indoor concentrations (house, school or workplace, other), outdoors, and transport by meta-analysis method. The risk for $NO_2$ and $O_3$ were assessed by hazard quotient using reference concentrations 30 and 60 ppb, respectively. The risk assessments were conducted through 1,000,000 Monte-Carlo simulations for probabilistic analysis. Results: Preschool children, students, housewives, workers, and seniors spent 91.9, 86.0, 79.8, 82.2, and 77.3% of their day in a house, school, or workplace, respectively. The risk assessment for the lifetime of a housewife and a worker showed that 33.8 and 28.4% of hazard quotients of $NO_2$ exceed 1, respectively, and more than 99% of hazard quotient of $O_3$ were less than 1. Conclusions: The risk of $NO_2$ and $O_3$ by sub-population group and for the lifetime of housewives and workers were assessed. The risk for $NO_2$ was higher than for $O_3$ and showed a different risk by sub-population group. Both $NO_2$ and $O_3$ showed a higher risk for housewives than for workers. This study can be used as a basis for lifetime exposure and risk assessment for $NO_2$ and $O_3$.

• 재활복지
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• v.21 no.1
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• pp.141-171
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• 2017

The purpose of this study is to investigate the job experience of the life rehabilitation teacher who is working in the residence with mental retardations. The purpose of this study is to suggest the intervention plan that can enhance the capacity of the living rehabilitation teachers and seek improvement points of residence institution of mental retardation. The results of this study show the meaning of experience in the job performance of the welfare facility workers. Through in -depth interviews through the candid stories of the research participants during the research, meaningful results could be obtained. There are 7 workers who participated in the study who worked in the institute for more than a year. Four sections are categorized made of 15 sub-categories constituted by 60 subjects collected by significant worker's answers. Four categories are the beginning of life rehabilitation teacher, adaptation as a life rehabilitation teacher, the pain of life rehabilitation teacher, the growth and the wish. The results of this study are expected to contribute to the improvement of the professionalism of the life rehabilitation teacher. It will also contribute to the development of the operation of residential facilities for people with mental retardation.

• 재활복지
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• v.20 no.4
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• pp.107-134
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• 2016

The primary purpose of this study is to develop a quality of life scale for adults with developmental disabilities and to test its validity and reliability. For this purpose, the authors generated a initial item pool composed of 62 items based on the conceptual model of Felce and Perry (1995). The initial items were evaluated by three reviewers, and then the items were revised based on their feedbacks. Utilizing a survey questionnaire including the scale items, data on 430 adults with developmental disabilities were collected in collaboration with 33 social welfare agencies and residential facilities for people with disabilities. Through descriptive analysis, correlation analysis, and relevant theories, the qualities of each item were examined, and then the best 20 items were selected. Cronbach's ${\alpha}$ for the final scale was .87. The results of confirmatory factor analysis showed that the 5-factor model fitted the data reasonably well, In addition, criterion validity of each subfactor of the scale was successfully established, employing t-test, one-way ANOVA, and correlation analysis. In discussion, implications and limitations of this study were examined.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.667-675
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• 2021

The purpose of this study is as follows: First, to analyze the spatial structure of Jeju by analyzing the rate of parking demand and supply; Second, to determine the parking service imbalance between regions; and third, to elucidate the causes of this spatial structural parking service imbalance and provide effective measures. Due to the rapid population and tourism growth, Jeju is suffering from traffic congestion and serious parking problems. For this, the ways to efficiently utilize the existing parking spaces were identified through spatial structure analysis based on the parking demand and supply in the Jeju area. As short-term policy, the following changes were proposed: switching to small-scale eup or myeon blocks of parking space, use of shared parking system, and repairing side streets in residential areas. As mid-to-long-term policy, it is linked to other means of transportation as follows: parking demand management policy through modal share by reorganizing public transportation routes or expanding traffic facilities; securing park-and-ride lots; and different parking pricing for different time periods. To implement these policies, each area of the public sector, private sector, and private-public partnership should develop the bond of sympathy by areas and participants.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.457-467
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• 2021

This paper aims to analyze changes in urban space use due to social distancing measures for COVID-19 using de facto population data in Seoul during daytime, which is estimated by Seoul Metropolitan Government and telecommunication company of KT using public big data and LTE signal data. The result of kernel density estimation and spatial autocorrelation analysis shows that the distribution patterns of de facto population in 2019 and 2020 were generally similar. This is a result of showing that the government's social distancing measures enabled a certain level of normal activities while suppressing the spread of COVID-19. However, analyzing de facto population subtracting 2019 from 2020 showed different results at the micro level. De facto population decreased in commercial areas but increased in residential areas. This means that COVID-19 social distancing measures had spatially uneven effect. The results of analyzing the effect of regional, land use, economic, educational, and accessibility characteristics on the changes of de facto population using spatial regression analysis are as follows. The higher the density of commercial facilities, the more businesses subject to regulations and schools and universities that require non-face-to-face classes, the more de facto population decreased. Conversely, it was found that de facto population increased in areas with many houses and parks due to telecommuting.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.883-896
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• 2023

As human activities in Korea are spread throughout the mountains, forest fires often affect residential areas, infrastructure, and other facilities. Hence, it is necessary to detect fire-damaged areas quickly to enable support and recovery. Remote sensing is the most efficient tool for this purpose. Fire damage detection experiments were conducted on the east coast of Korea. Because this area comprises a mixture of forest and artificial land cover, data with low resolution are not suitable. We used Sentinel-2 multispectral instrument (MSI) data, which provide adequate temporal and spatial resolution, and the k-nearest neighbor (kNN) algorithm in this study. Six bands of Sentinel-2 MSI and two indices of normalized difference vegetation index (NDVI) and normalized burn ratio (NBR) were used as features for kNN classification. The kNN classifier was trained using 2,000 randomly selected samples in the fire-damaged and undamaged areas. Outliers were removed and a forest type map was used to improve classification performance. Numerous experiments for various neighbors for kNN and feature combinations have been conducted using bi-temporal and uni-temporal approaches. The bi-temporal classification performed better than the uni-temporal classification. However, the uni-temporal classification was able to detect severely damaged areas.