• 환경생물
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• 제21권3호
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• pp.240-244
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• 2003

Conidia of molds within the Asian dust were captured in the ambient air of mid-west Korea, in springtime of 2000~2002. An eight-stage Cascade impactor and 0.22 $\mu\textrm{m}$ pore size membrane filters were used for the dust samples. Several kinds of molds grown from the samples were identified to the genus level. Those are Aspergillus, Basipetospora, Epicoccum, Fusarium, Monotospora and Penicillium. Relatively diversified mycelia of hyphomycetes were grown on the fine dust sample (1.1~2.1 $\mu\textrm{m}$) in the first year Asian dust episode (23~24 March, 2000). On the other hand, some fluffy molds and dark molds aggregations were grown on even the backup particle sample less than 0.43 $\mu\textrm{m}$ during the second year episode (24~26 April, 2001). The result of the last year episode (21~22 March, 2002) showed various mycelia grown on the sample contained from 1.1 to 2.1 $\mu\textrm{m}$ sized particles, just like the result of the first year episode (23~24 March, 2000). These variations between the episodes might be caused by the difference of the dust origins.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.19.1-19.10
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• 2014

Objectives Lysosome is the cell-organelle which is commonly used as biomonitoring tool in environmental pollution. In this study, the lysosomal proteomic of the yeast Saccharomyces cerevisiae was analyzed for utilization in the detection of toxic substances in mine water samples. Methods This work informs the expression of lysosomal proteomic in yeast in response with toxic chemicals, such as sodium meta-arsenite and tetracycline, for screening specific biomarkers. After that, a recombinant yeast contained this biomarker were constructed for toxic detection in pure toxic chemicals and mine water samples. Results Each chemical had an optimal dose at which the fluorescent protein intensity reached the peak. In the case of water samples, the yeast showed the response with sample 1, 3, 4, and 5; whereas there is no response with sample 2, 6, and 7. Conclusions The recombinant yeast showed a high ability of toxic detection in response with several chemicals such as heavy metals and pharmaceuticals. In the case of mine water samples, the response varied depending on the sample content.

• Geomechanics and Engineering
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• 제37권4호
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• pp.359-370
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• 2024

The primary goal of this study is to evaluate the migration of fine granular materials into overlying layers under cyclic loading using a modified large-scale triaxial system as a physical model test. Samples prepared for the modified large-scale triaxial system comprised a 60 mm thick gravel layer overlying a 120 mm thick subgrade layer, which could be either tailings or railway sand. A quantitative analysis of the migration of fine granular materials was based on the mass percentage and grain size of migrated materials collected in the gravel. In addition, the cyclic characteristics, i.e., accumulated axial strain and excess pore water pressure, were evaluated. As a result, the total migration rate of the railway sand sample was found to be small. However, the total migration rate of the sample containing tailings in the subgrade layer was much higher than that of the railway sand sample. In addition, the migration analysis revealed that finer tailings particles tended to be migrated into the upper gravel layer easier than coarser tailings particles under cyclic loading. This could be involved in significant increases in excess pore water pressure at the last cycles of the physical model test.

• 천문학회보
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• 제41권1호
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• pp.32.4-33
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• 2016

Recent studies suggest that the difference between global and local properties of galaxies (the local-global environmental (LoG) bias) might be important in the Type Ia supernova (SN Ia) host galaxy studies. Obtaining local spectroscopic properties of hosts at high redshift, however, is challenging. Here we will introduce a more efficient way to conduct this study by only using photometric data. We find that when we restrict a sample to the hosts whose stellar mass is less than $10^{10}$ $M_{\odot}$, a sample without LoG bias is efficiently selected. From the sample without LoG bias, we confirm that SNe Ia in locally star-forming environment are $0.103{\pm}0.010mag$ and $0.085{\pm}0.012mag$ fainter than those in locally passive region, for MLCS2k2 and SALT2, respectively. Because of ~6 times larger sample that covers much wider redshift range, our results are far more significant statistically, $10.3{\sigma}$ for MLCS2k2 and $7.1{\sigma}$ for SALT2, than previous results.

• The Journal of Asian Finance, Economics and Business
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• 제9권2호
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• pp.347-353
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• 2022

Using the Heckman two-step procedure, this study investigates the relationship between management accounting implementation and firm effectiveness. The research data for this study was acquired from 450 publicly traded companies in Vietnam; however, the final sample only includes 304 responses containing useful information. The reliability analysis was used to evaluate the acquired data to examine the qualities of constructs and the dimensions that make them up. Then, the Heckman two-step technique was performed to analyze the causal connection from the acceptance of management accounting to firm effectiveness allowing for the effect of environmental uncertainty and organizational characteristics on the likelihood of adopting management accounting. The empirical findings show that management accounting acceptance determines firm effectiveness; however, the research model on the relationship between management accounting adoption and firm effectiveness has a sample selection bias. The main conclusions of this study are that there is a difference in the effects of management accounting adoption on business effectiveness when sample selection bias is not taken into consideration. When potential sample selection bias is taken into account by integrating environmental uncertainty and organizational characteristics in the research model, the effect of adopting management accounting on company effectiveness becomes minor.

• 분석과학
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• 제22권5호
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• pp.369-375
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• 2009

저농도 섬유상 분진 표준시료를 제조하여 균질도와 정확성을 조사하고, 모의 숙련도 시험을 통해 최적의 숙련도 시험 방안을 평가하였다. 분석 결과 표준시료 농도와 석면밀도의 상관성이 0.9863~0.9968으로 매우 높게 나타났고, 표준시료를 이용한 모의 숙련도 시험을 통해서, 국내에서의 숙련도 시험 결과 평가 기준은 표준시료 분석결과의 Z값이 ${\mid}Z{\mid}{\leq}2$를 만족하는 것이 타당한 것으로 나타났다.

• 한국환경보건학회지
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• 제30권5호
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• pp.427-431
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• 2004

The calcination characteristics of the waste Corbicula Japonica and Ostrea virginjca shell were examined for the future use as desulfurization sorbent. The weight variation was measured according to thermal-decomposition using TGA and observed variation of the phase. The qualitative and quantitative analysis of the sample were performed using XRD and the structural analysis, SEM. The results of TGA and XRD experiments showed that the almost all of the raw samples Corbicula Japonica and Ostrea virginjca were changed from calcite to lime by firing and calcination reaction. The result of SEM experiment showed that the plate type of the raw sample was changed to circle type, so the surface area ratio was increased. Above results suggested that waste Corbicula Japonica and Ostrea virginjca were usable in the viewpoint of the reuse of resource and the decrease of environmental pollution.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3755-3759
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• 2010

A on-line SPE (solid phase extraction)-HPLC preconcentration method was developed for the determination of phenolic compounds at trace levels in environmental water sample. XAD-4 and Dowex 1-X8 were used as sorbent in the on-line SPE-HPLC method for the selective enrichment of nine phenolic compounds, which are included in the priority pollutants list of the US EPA. Also alumina prefiltering considerably reduced the amount of interfering peaks due to humic substances that could accumulated due to the preconcentration step and prevent quantification of polar phenolic compounds in environmental water samples. This method was used to determine the phenolic compounds in tap and river water and superiority to the US EPA 625 method in its enrichment factor, pretreatment time, recoveries, and detection limit. The limits of detection were in the range of $0.3-0.9\;{\mu}g/L$ in tap water sample.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.72-80
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• 2010

Possibility of the usage of sludge generated in coal mine drainage treatments as a briquette additive was investigated by the combination of industrial, elemental, and combustion experiments. A series of briquettes having 2% and 6% of sludge were used for the experiments. Compared to the control sample, our results show that all experimental values for the briquettes are very similar. In particular, it is worthy to note that there is no obvious difference in calorific values for the briquettes containing 2% or 6% of sludge. The calorific values are 4,250~4,360 kcal/kg, 4,240~4,250 kcal/kg, 4,180~4,210 kcal/kg, and 4,270~4,360 kcal/kg for the control sample, briquette containing 6% of Hambaek sludge, briquette containing 6% of Hamtae sludge, and briquette containing 2% of Hambaek sludge, respectively. Results of ash fusion temperature show that the temperature is greater than $1,550^{\circ}C$ for the control sample. However, the temperature for the briquettes with 6% of Hambaek sludge and 2% of Hambaek or Hamtae sludge is $1,510^{\circ}C$. For a briquette containing 6% of Hamtae sludge, the temperature of ash fusion is $1,530^{\circ}C$. After combustion, environmental impacts of the briquettes with sludge were tested. Little environmental influence was observed for the combusted briquettes with sludge.

• 환경영향평가
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• 제30권3호
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• pp.155-163
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• 2021

환경영향평가의 훼손수목량은 온실가스 배출량, 임목폐기물 산정 등 다양한 부분에 활용되는 환경지표이다. 지금까지 훼손수목량은 식생조사표의 임목밀도에 의존하였고, 이에 따른 표본편향으로 훼손수목량 추정의 불확실성이 가중되었다. 훼손수목량 추정의 정확성을 높이려면 전수조사를 대안으로 제시할 수 있으나 불가능한 것이 현실이다. 대안으로 드론영상을 이용한 개별 수목 탐지 방법이 있으며, 이 연구는 개별 수목 탐지 방법론으로 표본조사(방형구법)와 드론영상 분석법으로 추정된 훼손수목량을 전수조사 결과와 비교하였다. 연구 결과 전수조사 기준으로 드론 영상 분석법은 25주 과대추정 하였고 방형구법(평균)은 58주 과대 추정하였다. 그러나 기존 환경영향평가에서 시행하는 방형구법은 방형구의 개수, 방형구의 위치에 따른 표본편향의 영향을 많이 받을 것으로 예상된다.