• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.573-580
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• 2017

The oxicity assesment of Phenanthrene (PHE) has been investigated by using the rate (r) of survival and population growth in rotifer Brachionus plicatilis. The survival rate was determined after 24 h of exposure to PHE. The survival rate of PHE had no effect at a maximum of $300mg\;L^{-1}$. The r was determined after 72 h of exposure to PHE. It was observed that r in the controls (absence PHE) was greater than 0.5, but that it suddenly decreased with an increased concentration of PHE. PHE reduced r in a dose-dependent manner and a significant reduction occurred at a concentration of greater than $37.5mg\;L^{-1}$. The $EC_{50}$ value of r in PHE exposure was $63.7mg\;L^{-1}$. The no-observed-effect-concentration (NOEC) of r in PHE exposure was $18.8mg\;L^{-1}$. The lowest-observed-effect-concentration (LOEC) of r in the PHE exposure was $37.5mg\;L^{-1}$. From the results, the concentration of PHE (greater than $37.5mg\;L^{-1}$) has a toxic effect on the r of B. plicatilis in natural ecosystems. These results(including NOEC, LOEC and $EC_{50}$) might be useful for the Polycyclic aromatic hydrocarbons(PAHs) toxicity assessment in marine ecosystems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.391-397
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• 2008

This paper analyzes the spatial patterns of population distribution in Seoul Metropolitan Area in terms of spatial association using spatial statistics and spatial exploratory technique. Our empirical analysis based on global index shows that, in Seoul Metropolitan Area, the population had been distributed with strong positive spatial association over the period of 1980-2005. It implies that the population of each region is affected by the population distribution of adjacent regions. In addition, the analysis using local index was conducted for detecting the local patterns of spatial association, and the result shows that the clusters of population had been moved in the direction of West(Incheon and Bucheon) and South(Anyang and Seongnam) of Seoul where a large scale of lands or towns were developed over the period. These results will be the preliminary data for establishing management and development plans of Seoul Metropolitan Area.

• Journal of Environmental Health Sciences
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• v.44 no.4
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• pp.380-390
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• 2018

Objective: A significant association between blood lead levels and hypertension has been reported in many studies. The relationship between cadmium and hypertension has been debated as well. We aimed to study the association of lead, cadmium, and both with hypertension in the Korean general population. Methods: We examined 5,967 adult men and 6,074 women who participated in the Korea National Health and Nutrition Examination Survey III-VI (2005, 2008-2013 years). Logistic regression models were used to examine the relationship between blood lead concentration and blood cadmium concentration and hypertension using logtransformed blood lead and cadmium concentrations as independent variables after covariate adjustment. Results: Adjusted for general characteristics, the odds ratio of log-lead to hypertension was 2.71 (1.82-4.03), and log-cadmium to hypertension was 2.52 (1.83-3.47). Estimates were found to be statistically significant (p<0.001). When a multiple logistic model was applied, the odds ratio of log-lead and log-cadmium for hypertension were 2.24 (1.50-3.36) and 2.24 (1.62-3.10), respectively. The standardized estimate coefficients of log-lead and logcadmium for hypertension were 4.77 and 6.65, respectively. Conclusion: We observed the association of blood lead concentration, blood cadmium concentration, and both with hypertension. This study suggests that exposure to lead and exposure to cadmium are both risk factors for hypertension.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.267-273
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• 2000

In order to understand the impact for decomposition of blue-green algae Microcystis on water quality, the algae were cultivated with collection of natural population during approximately one month, when water-bloom of Microcystis dominated at August 31, 1999 in the lower part of the Okchon Stream. The enrichment of inorganic NㆍP nutrients didn't in algal assay and the effect of Microcystis on water duality was assessed from the variation of nutrients by algal senescence. Microcystis population seemed to play a temporary role of sink for nutrients in the water body. Initial algal density of Microcystis was 2.3×10/sup 6/ cells/㎖. When Microcystis population died out under light condition, algal NㆍP nutrients between 9∼12 days affected to increase of biomass after reuse by other algal growth as soon as release to the ambient water. However, cellular nutrients under dark condition were almost moved into the water during algal cultivation. NH₄, NO₃ and SRP concentration were highly increased with 160, 17 and 79 folds, respectively relative to the early. As a result, the senescence of Microcystis population seemed to be an important biological factor in which cause more eutrophy and increase of explosive algal development by a lot of nutrients transfer to water body. There are significantly observed an effort of reduce for production of inner organic matters such a phytoplankton as well as load pollutants from watershed in side of the water quality management of reservoir.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.545-546
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• 2006

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2007.10a
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• pp.81-82
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• 2007

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.6
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• pp.86-98
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• 2009

This study was carried out to investigate vegetation structure and soil properties of Adenophora racemosa population distributed in Jeombongsan, Seoraksan, Odaesan and Dutasan in Gangwon-do, Korea. From August 2007 until September 2009, $2m{\times}2m$ quadrate was established in native area of Adenophora racemosa in order to record a dominants and coverage, and soil factors at 22 sites. It was found that the altitude in the distributed areas for Angelica gigas population was 800 m or more. Adenophora racemosa population was classified into Rhododendron mucronulatum dominant population, Geranium var. hirsutum dominant population, Caret siderosticta dominant population and Aruncus dioicus var. kamtschaticus dominant population. In the site of study, soil pH, electrical conductivity, soil organic matter, available phosphorous, and exchangeable potassium, exchangeable calcium, exchangeable magnesium, exchangeable sodium concentration and total nitrogen were ranged from 5.0~7.1, 0.06~0.65dS/m, 0.96~8.94%, 12.3~32.8mg/kg, 0.12~0.89cmol+/kg, 0.34~10.08cmol+/kg, 0.1~l.4cmol+/kg, 0.02~0.29cmol+/kg and 0~8.4% respectively. According to the results of DCCA, Adenophora racemosa population were distributed in the high available phosphorous and exchangeable potassium, and Rhododendron mucronulatum dominant population was situated on low available potassium and high slope degree, Geranium var. hirsutum dominant population was high altitude, electrical conductivity and exchange magnesium, and Carex siderosticta dominant population and Aruncus dioicus var. kamtschaticus were distributed on high total nitrogen, organic matter, available phosphorous.

• Environmental Analysis Health and Toxicology
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• v.14 no.4
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• pp.203-216
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• 1999

This paper describes a set of multi-pathway models for estimating health risk to lead. The models link concentrations of an environmental contaminant (lead) in air, water and food to human exposure through inhalation, ingestion, and dietary routes. Exposure is used as the foundation for predicting risk of health detriment within the population. The process of estimating exposure using often limited data and extrapolating to a large diverse population requires many assumption, inferences, and simplification. This paper is divided into four section. The first section provides lead contaminant levels on obtaining environmental concentration of air, tap water, and foods. The second section provides a discussion of exposure parameters and uncertainty associated predicting human health risk of contaminants. The third and fourth section illustrate lifetime average daily exposure (LADE) and excess cancer risk (ECR) based on exposure parameters. The relationship between concentration of lead in an environmental medium and human exposure is determined with pathway exposure factors (PEFs). The calculation of LADE and ECR is carried out using Monte-Carlo simulation with probability density function of exposure parameters. Examination of the result reveals that, for lead exposure, ingestion (food) is the dominant route of exposure rather than inhalation (air), and ingestion (tap eater).

• International Journal of High-Rise Buildings
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• v.6 no.4
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• pp.327-332
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• 2017

This paper discusses several topics associated with the densification caused by supertall buildings and their impact on city systems. The paper covers five key areas where a supertall tower creates a concentration of needs and effects. First, the paper comments on population shifts towards the city and how they affect carbon footprint, utilities infrastructure and transport. The effect of single- and mixed-use towers is discussed in the context of population density. The second section brings the issues of transit, accessibility and master planning into focus. The use and criticality of public transport, cycling and walking is described. Servicing and deliveries using freight consolidation and shared systems is also discussed along with their contribution to the culture of sustainable travel. In the third section the paper reflects on supertall buildings' below-ground utilities and drainage provision, particularly the challenges faced in established city infrastructures. The utilities issues associated with supertall concentration (in land-use terms) compared to equivalent low-rise distribution is also commented on in the context of surface water runoff. In the fourth section, the topic of supertall sustainability is discussed and how city systems need to respond to create desirable and affordable space for occupiers. The changing need for vertical communities, 'stacked neighbourhoods' and the notion of a micro-city is described. Finally, the paper considers the energy consumption and resilience of supertall buildings in the context of basic geometry, façade design, climate and mixed-use benefits as they impact city systems.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.19-26
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• 2010

Batch experiments were conducted to investigate growth and nutrient removal performance of microalgae Chlorella vulgaris by using piggery wastewater in different concentration of pollutants and the common growth models (logistic, Gompertz and Richards) were applied to compare microalgal growth parameters. Removal of nitrogen (N) and phosphorus (P) by Chlorella vulgaris showed correlation with biomass increase, implying nutrient uptake coupled with microalgae growth. The higher the levels of suspended solids (SS), COD and ammonia nitrogen were in the wastewater, the worse growth of Chlorella vulgaris was observed, showing the occurrence of growth inhibition in higher concentration of those pollutants. The growth parameters were estimated by non-linear regression of three growth curves for comparative analyses. Determination of growth parameters were more accurate with population as a variable than the logarithm of population in terms of R square. Richards model represented better fit comparing with logistic and Gompertz model. However, Richards model showed some complexity and sensitivity in calculation. In the cases tested, both logistic and Gompertz equation were proper to describe the growth of microalgae on piggery wastewater as well as easy to application.