• Membrane and Water Treatment
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• v.10 no.6
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• pp.395-404
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• 2019

The influence of chlorine on marine bacterial communities was examined in this study. A non-chlorine-adapted marine bacterial community (NCAM) and a chlorine-adapted bacterial community (CAM, bacterial community treated with $0.2mg-Cl_2/L$ chlorine) were cultivated for 1 month. A distinct difference was observed between the NCAM and CAM, which shared only eight operational taxonomic units (OTUs), corresponding to 13.1% of the total number of identified OTUs. This result suggested that chlorine was responsible for the changes in the marine bacterial communities. Kordiimonas aquimaris was found to be a chlorine-resistant marine bacterium. The effect of intermittent chlorination on the two marine biofilm communities formed on the reverse osmosis (RO) membrane surface was investigated using various chlorine concentrations (0, 0.2, 0.4, 0.6 and 0.8 mg $Cl_2/L$). Although the average number of adherent marine bacteria on the RO membrane over a period of 7 weeks decreased with increasing chlorine concentration, disinfection efficiencies showed substantial fluctuations throughout the experiment. This is due to chlorine depletion that occurs during intermittent chlorination. These results suggest that intermittent chlorination is not an effective disinfection strategy to control biofilm formation.

• Journal of the Korean housing association
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• v.19 no.1
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• pp.57-66
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• 2008

In the past, strong social bands, which had spontaneous communities, existed in Korean traditional society. However, while it's developing through industrialization; monolithic apartment houses were introduced which causes less interaction between neighbors. With the growing attention to the higher living quality, various schemes to revitalize the community spirits have been groped, including to improve in hardhearted neighborhood relationships and to cope with the dreariness in the city. With the development of the internet and the spread of 'digital home', the communities in cyber space have been especially revitalized since the information-oriented society. In a move to strengthen the communities in apartment complexes, this study tries to find the revitalization scheme for virtual communities in apartment complexes by analyzing the contents of its web sites and understanding the world of virtual community. These are compared and analyzed. The related virtual communities ("cafe" or "blogs") are also analyzed. The results are as follows. 1) There are some differences among the contents provided by apartment virtual community developing companies, still, it could be categorized into four types; "apartment complex introduction and management information" "community revitalization" "living guide" "individual services" 2) The contents provided by self-organized communities of residents neither require additional charge nor special membership for information while the formation is not systematized. 3) In the comparison of apartment virtual community developing companies with residents self-organized communities, "apartment complex introduction and management information" on freeboard, notice, request and Q&A, and "community revitalization" on communication board are both provided throughout the web sites. 4) The contents provided by apartment virtual community developing companies makes the information available in a wide range with managers, on the other hand, self-organized communities emphasize on showing attachment and concern of residents and requiring communications between neighborhoods.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.60-69
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• 1982

According to the distance from the industrial complex, 5 sample plots were selected to study the changes of vegetational composition of the forest community caused by air pollution in Ulsan. Then 5 subplots were set within a plot. We considered that this gradient analysis by distance could be coincided with the gradual transition of plant succession. Number of species, number of individuals, species diversity, evenness increased and similarity index decreased with increasing distance from the industrial complex. Robinia pseudoacacia, Smilax china appeared to be tolerant to air pollution whereas Quercus variabilis, Q-aliena, Q. dentata and Albizzia julibrissin to be sensitive.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.593-603
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• 2012

This study was carried out to investigate the ecological succession sere and conservative value, and to provide the basic data for the planning of the Provincial Park Management in Seonamsagol(Valley), Jogyesan(Mt.) Provincial Park(altitude 884m), Suncheon City, Korea by analysing the structure of the plant community. Twenty plots(size is $20m{\times}20m$) were set up at an altitude of range from 315m to 480m. As a result of analysis of TWINSPAN which is one of the ordination technique, the plant communities were divided into four groups which are community I(Quercus variabilis community), community II(Q. serrata community), community III(Decideous broad-leaved plant community), and community IV(Carpinus tschonoskii community). The warmth index is $104^{\circ}C{\cdot}month$ based on the data of monthly mean temperature during the past thirty years(1981~2010), so we found out that the vegetation of the study site located in the South Temperate Climate Zone. We supposed that the ecological succession sere of the study site is in the early stage of developing from Q. serrata community to Carpinus tshonoskii community, however we should do a long-term monitoring to investigate the changes of the ecological succession each plant community, meanwhile Sasa borealis was dominant species in the shrub layer. The diameter at breast height of specimen tree is range from 20 to 55cm(average 36cm) and the height of that is range from 14 to 35m(average 23cm). The age of community I was 64 years old, that of community II was from 59 to 64 years old, that of community III was from 51 to 62 years old, and that of community IV was from 41 to 68 years old, thus the age of the study site is about from 38 to 72 years old. According to the index of Shnnon's diversity(unit: $400m^2$), community IV was ranged from 0.8452 to 1.2312, community III was ranged from 0.8044 to 1.1404, community II was ranged from 0.8221 to 0.9971, and community I was 0.8324.

• Korean Journal of Community Nutrition
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• v.18 no.1
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• pp.77-87
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• 2013

This study was conducted to investigate the nutrient intakes of subjects by quartile of percent energy intake from cooked rice, consumption of cooked rice mixed with multi-grains and to evaluate rice consumption in relation to the risk of metabolic syndrome. The subjects were 5,830 males and females aged between 20~64 years based on 2007-2008 KNHNES data. Levels of percent energy intake from cooked rice were classified into 4 groups (Q1, Q2, Q3, Q4 groups: 25% of each) using data of 24-hour recall method from KNHNES. Using medical examination and questionnaire, subjects were classified according to diagnostic criteria of metabolic syndrome. The subjects with higher age, being married, lower education, lower economic level were more likely to take higher percent energy intake from cooked rice. Quartile Q3 of percent energy intake from cooked rice tended to show higher Index of Nutritional Quality (INQ) for fiber, calcium, iron, potassium and vitamin A. INQ of protein, dietary fiber, calcium, thiamin, phosphorus, potassium, riboflavin, niacin and vitamin C by consumption of cooked rice mixed with multi-grains was higher than that by consumption of cooked white rice when adjusted for age. No association with a risk for metabolic syndrome was found for quartile of percent energy intake from cooked rice or cooked rice mixed with multi-grains compared to cooked white rice after adjusting for energy, gender, age, BMI, alcohol, smoking, income and physical activity. In conclusion, consumption of over 54% energy intake from cooked rice or only cooked white rice showed relatively low INQs, but was not associated with a higher risk for metabolic syndrome.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.377-385
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• 2014

In this study, a wastewater treatment system for hypersaline wastewater utilizing the Hypersaline Wastewater Treatment Community (HWTC) has been developed. The hypersaline wastewater treatment efficiency and microbial community of the HWTC were investigated. The average removal efficiencies of chemical oxygen demand were 84% in an HRT of 2.5 days. Microbial community analysis, by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene fragments and 16S rRNA gene clone library, revealed community diversity. The 16S rRNA gene analysis of dominant microbial bacteria in 4% hypersaline wastewater confirmed the presence of Halomonas sp. and Paenibacillus sp. Phylogenetic analysis suggested that the taxonomic affiliation of the dominant species in the HWTC was ${\gamma}$-proteobacteria and firmicutes. These results indicate the possibility that an appropriate hypersaline wastewater treatment system can be designed using acclimated sludge with a halophilic community.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.73-82
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• 1988

This study was excuted to analyze the vegetational community structure of the Hongrudong valley the Mt. Gaya by three kinds of ordination techniques (polar, principal component analysis, reciprocal averaging). Eleven sites were sampled with the clumped method to analyze the vegetation structure. The result suggested that Hongrudong valley forest was divided by Pinus densiflora and Quercus aliena community. The relation between stand scores of ordination and soil pH, humus content, soil moisture had a tendency to increase significantly from P. densiflora to Q. aliena community. RA was the most effective method of this study. RA ordination was showed that successional trends of tree species seem to be from P. densijlora through Q. variabilis to Q. aliena, Carpinus laxiflora in the upper layer and from Lespedeza cyrtobotrva, Rhus spp., Rhododendron schlippenbachii through Fraxinus sieboldiana, Lindera obtusiloba to Euonymus oxyphyllus, Weigela subsessilis, Callicarpa japonica in the middle layer.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.24-38
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• 1996

This study was conducted to investigate the Ecobridge district which connects green corridor from Central park to Pulkoksan and to establish of ecological space through analysis of avifauna community, plant community structure. In the results of analysis of avifauna, 3 species 23 individuals(Pica pica, Parus major, [asser montanus) in Ecobridge district, 5 species 37 individuals(Peca pica, Parus major, Passer montanus, Oriolus chinensis, Hirundo rustica) in Central park forest. There were 15 species 72 individuals in Pulkoksan. The plant community structure were classified of three types. As divided types were artificial forest(Pinus rigida, P. koraiensis, etc.) natural forest(Quercus mongolica, Q. serrata, Q. acutissima, Q. spp.) and semi-natural forest, which have shown the successional trends from the artificial forest to Quercus spp. community. The Ecobridge district was used as the space for the passers-by owing to its the simple vegetation. Species diversity was appeared that there was the order of Ecobridge district$\longrightarrow$Central park forest$\longrightarrow$Pulkoksan forest. Similarity index was calculated 20~23% between Ecobridge district$\longrightarrow$Central park, Pulkoksan forest. Therefore the highest species diversity and multistratum vegetation structure of Pulkoksan were the most suitable for the establishment to ecological space in the district.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.468-476
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• 2014

The aim of this study was to examine whether there is an association between vitamin intakes and established periodontitis in Korean adult population. The 6,245 subjects aged over 19 years old, who participated in health survey, oral examination and nutrition survey were selected for this study from the database of the Fourth Korean National Health and Nutrition Examination Survey. Established periodontitis was defined as ${\geq}$ code 3 in community periodontal index. Vitamin intake was assessed with the food-frequency questionnaire. In analysis, participants were classified by quintile of vitamin intakes. We also considered covariates as socio-demographic characteristics, health-related behaviors including physical activities, systemic diseases and oral health-related behaviors. Multiple logistic regression was performed to assess the crude and adjusted associations. All analyses considered a complex sampling design using SAS 9.2. In crude analysis, less intake of vitamin A, retinol and vitamin B2 significantly increased the risk of periodontitis (vitamin A, odds ratio [OR] Q1=1.00, Q2=0.73, Q3=0.80, Q4=0.77, Q5=0.78; retinol, OR: Q1=1.00, Q2=0.86, Q3=0.73, Q4=0.62, Q5=0.55; vitamin B2, OR: Q1=1.00, Q2=0.70, Q3=0.63, Q4=0.67, Q5=0.68). However, after adjusting for socio-demographics, general and oral health status and behaviors, only vitamin B2 was significantly associated with established periodontitis (OR: Q1=1.00, Q2=0.72, Q3=0.73, Q4=0.76, Q5=0.84). An adequate vitamin B2 intake was significantly associated with a decreased risk of periodontitis. This finding shows that nutrient intake is slightly correlated with periodontitis in Korean adult population. Further studies are needed to understand this association between nutrients intake and periodontitis in more details.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.4
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• pp.33-42
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• 2000

This study is carried out to investigate plant community structure, actual vegetation map and flora for examining the relationship between naturally introduced vegetation and surrounding vegetation in Hamtae coal-mined spoil lands. According to the analysis of vegetation, surrounding vegetation was divided into five plant community groups : Pinus koraiensis community, Pinus densiflora - Quercus mongolica community, Q. mongolica - Deciduous broadleaved trees community, Betula schmidtii - B. davurica community, Larix leptolepis community. Robinia pseudo-acacia, which had been planted, was dominant species in coal-mined spoil lands. Young trees, which were naturally introduced, such as B. schmidtii, B. davurica etc., partially appeared with the high density($15{\sim}19ea/100m^2$) in coal-mined spoil lands. The flora of this area was listed as 54 taxa; 22 families, 42 genus, 50 species, 3 varieties and 1 forma. Especially Spodiopogon sibiricus, Miscanthus sinensis, Arundinella hirta, Artemisia capillaris, Artemisia iwayomogi and Youngia denticulata appeared with the high frequency. It is estimated that the proper way for harmonious and effective revegetation is to target B. schmidtii - B. davurica communities and to seed B. schmidtii - B. davurica mixing highly frequent herbaceous species.