• Journal of Korea Water Resources Association
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• v.46 no.4
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• pp.413-424
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• 2013

The TMDL, the watershed-oriented water quality management policy, was introduced to inhibit the total amount of pollutant loading generation, and to develop the region environmentally friendly. However, despite the implementation of TMDL, the water quality of Nam river downstream has worsened continuously since 2005. Diverse pollution sources such as cities and industrial zone are scattered around the Nam river. Eutrophication are caused due to deterioration of water quality by low velocity. BOD concentrations in the eutrophic waters affected by the incoming BOD and the autochthonous BOD by the production of phytoplankton. In this study, the quantitative relation of incoming BOD and autochthonous BOD was analyzed for water quality management. The influence of autochthonous BOD was analyzed using QUALKO2 and QUAL2E. Considering the effects of Chl.a, BOD concentration from QUALKO2 model simulations is higher than BOD concentration from QUAL2E model. The results of QUALKO2 showed higher correlation with the measured data. Autochthonous BOD needs to be managed to solve the water pollution problem of Nam river downstream, which is looking for ways to reduce Chl.a by using the increase of the dam outflow and the improvement of the water quality from WWTP.

• Journal of Environmental Health Sciences
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• v.43 no.5
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• pp.438-445
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• 2017

Objectives: The purpose of this study was to develop exposure factor data for the Korean child population, with a specific focus on behavior characteristics such as hand-to-mouth and object-to-mouth and an analysis of influential factors. Methods: We divided environments into two places, which were house/indoor and nursery. A total of 400 children (house/indoor) and a total of 162 children (nursery) were recruited from the cities of Seoul, Incheon, Daegu, and Gwangju. The children were divided into two groups. We conducted direct measurement by using one hour of videotaping alongside questionnaire surveys. This was performed to calculate behavior rates, such as how many children perform hand-to-mouth and object-to-mouth behaviors. Results: The respective average frequencies of hand-to-mouth and object-to-mouth were $0.8{\pm}2.23$ and $0.82{\pm}2.64contacts/hr$ for house/indoor. The respective average frequencies of hand-to-mouth and object-to-mouth were $2.87{\pm}4.63$ and $1.47{\pm}3.84contacts/hr$ in the nursery group. For the mouthing participants, the average frequencies of hand-to-mouth and object-to-mouth were 3.31 and 3.20 contacts/hr in house, and 4.80 and 3.26 in nursery. Compared to other countries such as the USA, the frequencies of hand-to-mouth and object-to-mouth behaviors found in this study were relatively lower. Conclusions: Children have the potential for exposure to toxic substances through non-dietary ingestion pathways by mouthing objects or their fingers. In this study, the mouthing frequency was relatively lower than that found in Western countries. This can be explained that mouthing behaviour may be affected by culture and lifestyle characteristics.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1447-1455
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• 2011

The purpose of this study was to analyze physicochmical characteristics of oil within planting base of Incheon coastal reclamation cities where 10 years have passed since reclamation, and to provide basic data to promote growth and development of plants by conducting evaluation based on the planting degree standard. Study targets were Cheongra, Sondo, and Yeongjong districts within Incheon Free Economic Zone, the coastal reclamation city. The analysis results of average soil characteristics of 3 districts. Soil acidity(pH) was shown in orders of Cheongra district(8.85) > Songdo district(8.70) > Yeongjong district(7.97) and electric conductivity(EC) was shown in orders of Cheongra district(4.80 dS/m) > Songdo district(1.30dS/m) > and Yeongjong district(0.07 dS/m). Organic matter content(OMC) was shown in orders of Cheongra district(5.72%) > Songdo district(2.60%) > Yeongjong district(0.59%) and available phosphate was shown in orders of Cheongra district(70.70 mg/kg) > Songdo district(23.07 mg/kg) > Yeongjong district(2.49 mg/kg). $K^+$ was shown in orders of Songdo district(0.84 cmol/kg) > Cheongra district(0.74 cmol/kg) > Yeongjong district(0.22 cmol/kg), $Ca^{++}$ was shown in orders of Cheongra district(22.08 cmol/kg) > Songdo district(9.87 cmol/kg) > Yeongjong district(4.04 cmol/kg), and $Mg^{++}$ was shown in orders of Cheongra district(1.98 cmol/kg) > Songdo district(1.22 cmol/kg) > Yeongjong district(1.12 cmol/kg). Planting base level of coastal reclaimed land can be applied with above intermediate level, soil acidity and available phosphate were all more than intermediate in 3 districts, and electric conductivity was low level in Cheongra district and more than intermediate level in Songdo and Yeongjong districts. Organic matters content was more than intermediate level in Cheongra district and low level in Songdo and Yeongjong district. $K^+$ among exchangeable ions was intermediate level in Cheongra and Songdo districut and low in Yeongjong district. $Ca^{++}$ and $Mg^{++}$ both were more than imtermidiate levels in 3 districts.

• Journal of the Economic Geographical Society of Korea
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• v.6 no.2
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• pp.443-470
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• 2003

This study is to consider economic, political, socio-cultural and environmental characteristics of the new urbanization process and its spatial structures and urban policy of Seoul in the 1990s. Some experimental findings which have been identified throughout this study can be summarized as follows. First of all, Seoul, the largest city in S.Korea has experienced a restructuring process of economy, which has been promoted by the development of producer services as well as knowledge- based or high tech industries. Secondly, the autonomy of Seoul has increased after the introduction of local self-government, with relatively higher self-management of local finance than other cities, strengthening the tendency of enterpreneurialism, empowering civil movements, and increasing the political participation of women. Thirdly, in the socio-cultural aspect, the material wants to gain a certain identity through consumption, using urban environments culturally, varying consuming attitudes and ways of leisure times in relation with the rapid development of transportation and information communication. Fourthly, in the environmental aspect, Seoul has tried to introduce the concept of sustainable development in terms of increasing wants on the quality of life, and to develop a pro-environmental eco-city with environmental rehabilitation, constructing green space and eco-park. Finally, in the spatial dimension, Seoul has shown a structuration of multi-centers, with highly spectacular urban landscapes and seemingly authentic urban planning. These results make us confirm that Seoul has been in the process of new urbanization which can be distinguished from the previous one.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.12
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• pp.1352-1370
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• 2010

In this paper, we investigated the shadow area of radio programs which are currently being broadcast via FM 102.5 MHz in Jeollabuk-do consisting of 6 cities and 8-guns. The field strength data of FM 102.5 MHz was used with criterion of shadow area. As a result, the field strength of the eastern mountainous area in Jeollabuk-do was very low. We also measured, compared and analyzed the field strength of 102.5 MHz(TBN-Jeonju), 100.7 MHz(KBS) and 99.1 MHz (MBC) in Jeollabuk-do. Based on the field strength data, we tried to find what correlation exists and how much influence is between difference of antenna output power and solution of shadow area. In result, enhancement of antenna output power is not solution in terms of reducing the shadow Area of 102.5 MHz(TBN-Jeonju). In addition, we measured, compared and analyzed the field strength of 102.5 MHz(TBN-Jeonju) and 106.9 MHz(EBS). In fact, the relay stations with 104.1 MHz, 104.9 MHz, 105.3 MHz and 107.5 MHz of EBS FM has a number of FM relay stations in the eastern mountainous area of Jeollabuk-do. As a result, we confirmed that EBS almost did not have shadow area in the eastern mountainous area of Jeollabuk-do based on the field strength data. As in the case of EBS and KBS, we suggest installing TBN-Jeonju FM relay station with the best solution to reducing the shadow area to extend the audible range of TBN-Jeonju.

• Journal of Environmental Policy
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• v.13 no.3
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• pp.43-73
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• 2014

Cities in Korea have rapidly urbanized and they are not well prepared for natural disasters which have been increased by climate change. In particular, they often struggle with urban flooding. Recently, green infrastructure has been emphasized as a critical strategy for flood mitigation in developed countries due to its capability to infiltrate water into the ground, provide the ability to absorb and store rainfall, and contribute to mitigating floods. However, in Korea, green infrastructure planning only focuses on esthetic functions or accessibility, and does not think how other functions such as flood mitigation, can be effectively realized. Based on this, we address this critical gap by suggesting the new green infrastructure planning framework for improving urban water cycle and maximizing flood mitigation capacity. This framework includes flood vulnerability assessment for identifying flood risk area and deciding suitable locations for green infrastructure. We propose the use of the combination of frequency ratio model and GIS for flood vulnerability assessment. The framework also includes the selection process of green infrastructure practices under local conditions such as geography, flood experience and finance. Finally, we applied this planning framework to the case study area, namely YeonJe-gu an Nam-gu in Busan. We expect this framework will be incorporated into green infrastructure spatial planning to provide effective decision making process regarding location and design of green infrastructure.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.300-309
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• 2001

The purpose of this study was to investigate the caries prevalence and caries pattern of preschool children in a small city. Six hundred twenty four kindergarten children in Milyang city were examined for their caries experience of individual teeth and surfaces by dmf index. The obtained results were as follows. 1. The rate of children with caries experience(dmft rate) in primary teeth was 74.0% in 3-year-olds, 83.8% in 4-year-olds, and 90.6% in 5-year-olds. The mean number of decayed, missed, and filled primary teeth(dmft index) was 3.47 in 3-year-olds, 5.41 in 4-year-olds, and 6.01 in 5-year-olds. 2. The caries prevalence of children in this study was higher than those of other researches in past and in other cities. 3. The caries-experienced teeth in order in 5-year-olds were as follows : mandibular 2nd primary molar, mandibular 1st primary molar, maxillary 2nd primary molar, maxillary primary central incisor and maxillary 1st primary molar. 4. The pattern of dental caries development was different between the incisors and molars. The prevalent surface of caries was proximal surface in primary incisors, but occlusal surface in primary molars.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.484-492
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• 2019

The aim of the present study was to compare the cold tolerance of seven different types of trees growing in southern Korea to select evergreen broad-leaved trees that can be used as street trees in large land areas experiencing climate change. The trees compared were the thorn tree, Cinnamomum camphora, Camellia japonica, Machilus thunbergii, Dendropanax morbifera, Daphniphyllum macropodum Miq., Quercus glauca Thunb., and Raphiolepis indica. When the trees were subjected to low temperature treatment, their electrolyte elution volume values appeared to increase with the decreases in the treatment temperature. The analysis of the cold tolerance of each type of tree was based on the estimated temperatures in the following order: C. japonica (-11.586℃) > R. indica (-9.348℃) > Q. glauca (-8.719℃) > M. thunbergii (-8.090℃) > D. macropodum (-7.409℃) > D. morbifera (-7.085℃) > C. camphora (-6.995℃). The relative cold tolerance difference found in the seven tree species was more than 5℃, as evaluated previously. In the Lauraceae family, the difference in cold tolerance was more than 2℃, even in the same species. The analysis showed that trees with excellent cold tolerance included Q. glauca Thunb., C. japonica, R. indica, and the thorn tree. This knowledge is required for the evaluation of the possibility of the survival of trees under cold temperature conditions in cities.

• Korean Journal of Social Welfare
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• v.69 no.3
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• pp.35-63
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• 2017

This study conducted researches to get related basic materials and grope for a way to prevent or treat suicidal ideation. For the researches, the study examined eco-systematical variables of suicidal ideation of those who are 65 years or older, and the influence of the change in the eco-systematical variables by using the source materials researched in sixteen cities/provinces over the country from KOWEPS(Korea Welfare Panel Study), and then reviewed if there any difference according to whether they had suicidal ideation or thought in the previous year. The analysis result shows that each variable of the ecological system such as individual, family, and social system has an effect on the elderly's suicidal ideation, and there is difference in the influence factor according to whether they had suicidal ideation in the previous year or not. The result implies the policy to cope with the elderly's suicide needs multidimensional approach of individual, family, and society rather than a simple individual level. And also there should be a different support or service according to their situation or conditions like previous suicidal ideation. Especially, it is quite significant that the factors do not influence the elderly who had suicidal ideation in the previous year, but have an effect on those who did not have any suicidal ideation, which means that the proactive and preventive support related to suicidal ideation would guarantee a more efficient and effective policy.

• Journal of the Korean Geographical Society
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• v.36 no.5
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• pp.561-577
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• 2001

Urban spatial structure is closely related to the spatial distribution of urban economic activities. The spatial distribution pattern is no more than an aggregated expression of the location and/or relocation behavior of individual firms and establishments. In this respect, it is important to identify and examine the factors that affect the spatial behavior of individual firms for a more comprehensive understanding of urban space. Agglomeration economies are one of the most prominent urban economic phenomena in the modern metropolitan area. Most firms in an urban space seek external economies through the spatial clustering of their activities. Agglomeration economies feature prominently in the analysis of urban economic structure across urban areas. While the agglomeration economies between cities focus at the macro-scale of analysis, such economies within any given city focus more on the micro geographical scale. There have been a number of researches on agglomeration economies, among which there are relatively few approaches based on an intra-urban context. This proper explores the agglomeration economies at the micro scale and tries to reseal the spatial realization of the agglomeration economies within and between sectors. Three sectors are considered in the analysis; manufacturing, retail and service. The model is based on simultaneous equation systems combined with spatially weighted variables and estimated by the KRP estimators.