• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.3
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• pp.96-107
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• 1997

This study was carried out to examine the physicochemical characteristics of dredged soils in reservoirs. Surveys and analyses of basic materials were made on 241 of 2,328 reservoirs in Chonbuk province through 2 years from December 1994 to November 1996. The results of this study are summarized as follows : 1. Soils were classified as 15 types according to physical properties, and some soils contain comparatively high percentage of sand and gravel. Considering only soil textures, useful and economical soils as aggregate are approximately 25% in all, and the other soils are arable for farm planting. 2. The results of chemical analyses of soils showed on the average 5.9 in pH, 1.lmmhos/cm in ECe, 14.6me/l00g in CEC, 460.0ppm in T-N, 119.0ppm in T-P, 264.9ppm in K, 134.2ppm in Na, l,335.0ppm in Ca, 575.9ppm in Mg, 486.Sppm in Fe, 57.7ppm in Mn, 3.3ppm in Cu, 21.9ppm in Zn, 0.49ppm in As, 0.34ppm in Cd, 0.O3ppm in Hg, 1.7% in OM, respectively. 3. General chemical components, heavy metals, organic matter contents were analyzed as similar to tlie mean values of common soils, therefore it was considered to be no significant effects on crop growth in the chemical properties. 4. Accodingly, the physicochemical characteristics of soils ought to be analyzed accurately before dredging for effective using of dredged soils. And it will be more effective, if the dredged soils are used with proper balance among each content of components with considering to the physicochemical properties of common soils.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.91-96
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• 2003

To monitor the heavy metal exposure conditions of Feral Pigeons Columba livia, we collected them at commercial area, industrial area, park area and resident area in Seoul. In feathers, iron concentrations were significantly different among habitats(ANOVA, p<0.05), and were the highest at park area. Manganese concentrations were relatively higher at industrial and park area than other areas(ANOVA, p<0.05). In case of copper levels were the significantly highest at park area(ANOVA, p<0.05). Zinc, lead and cadmium had no difference among habitats. Correlation between livers and feathers concentrations were highly significant to copper(r²=0.983, p<0.01) and cadmium(r²=0.632, p<0.01), but iron, zinc, manganese and lead were not significantly different.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.285-285
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• 2010

$Cu(In,Ga)Se_2$ (CIGS) 박막 태양전지 제조에는 동시증발법 (co-evaporation)으로 Cu, In, Ga, Se 각 원소의 증발을 세 단계로 제어하여 CIGS 박막을 증착하는 3-stage 방법이 널리 이용된다[1]. 3-stage 중 1st-stage에서는 In, Ga, Se 원소 만을 증발시켜 $(In,Ga)_2Se_3$ 전구체 (precursor) 박막을 성장시킨다. 고효율의 CIGS 태양전지를 위해서는 $(In,Ga)_2Se_3$ 전구체 증착의 공정 변수와 이에 따른 박막 특성의 이해가 중요하다. 본 연구에서는 Mo 박막이 증착된 소다석회유리 (soda lime glass) 기판에 동시증발장비를 이용하여 280 380 의 기판 온도에서 In, Ga, Se 물질을 증발시켜 $(In,Ga)_2Se_3$/Mo/glass 시료를 제작하였으며 XRD, SEM, EDS 등의 방법을 이용하여 특성을 분석하였다. XRD 분석 결과 기판 온도 $280{\sim}330^{\circ}C$에서는 $(In,Ga)_2Se_3$ 박막의 (006), (300) 피크가 관찰되었으며, 기판 온도가 증가할수록 (006) 피크 세기는 감소하였고 (300) 피크 세기는 증가하였다. $380^{\circ}C$에서는 (110)을 포함한 다수의 피크가 관찰되었다. 그레인 (grain) 크기는 기판 온도가 증가할수록 커지며 Ga/(In+Ga) 조성비는 기판 온도에 따라 일정함을 각각 SEM과 EDS 측정을 통해 알 수 있었다. $(In,Ga)_2Se_3$ 전구체의 (300) 배향은 CIGS 박막의 (220/204) 배향을 촉진하고[2], 이것은 높은 광전변환효율에 기여하는 것으로 알려져 있다. 때문에 $(In,Ga)_2Se_3$의 (300) 피크의 세기가 가장 큰 조건인 $330^{\circ}C$를 1st-stage 증착 온도로 하여 3-stage CIGS 태양전지 공정을 수행하였으며, $MgF_2$/Al/Ni/ITO/i-ZnO/CdS/CIGS/Mo/glass 구조의 셀에서 광전변환효율 16.96%를 얻었다.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.86-94
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• 2015

Chironomous is aquatic insect belonging to order Diptera, family Chironomidae. Their larval stage can be found mainly in aquatic benthic environment, hence good model organism to study environmental toxicology assessments and consider as useful bio indicators of contamination of the aquatic environment. In this study, Chironomus Heat Shock Proteins, Cytochrome 450, Glutathione S-transferase, Serine-type endopeptidase gene expressions were compared between polluted field areas (Chironomus plumosus) and under laboratory conditions (Chironomus riparious) to investigate molecular indicators for environmental contaminant stress assessment. Heavy metal (Al, Fe, Mn, Cu, Cr, Zn, Se, Pb, As, Cd) concentrations in sediments collected from three study areas exceeded the reference values. Moreover, HSPs, CYP450 and GST gene expression except SP for C. plumosus showed higher expression than C. riparious gene expression. Similar gene expression pattern was observed in C. riparious that exposed environment waters up to 96 h when compared to C. plumosus exposed to waters that grown in lab conditions. In summary, this comparative gene expression analysis in Chironomous between field and laboratory condition gave useful information to select candidate molecular indicators in heavy metal contaminations in the environment.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.13-26
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• 2018

This research was conducted to elucidate the removal mechanism of heavy metals and sulfate ion from acid mine drainage(AMD) by porous zeolite-slag ceramics (ZS ceramics) packed in a column reactor system. The average removal efficiencies of heavy metals and sulfate ion from AMD by the 1:3(Z:S) porous ZS ceramics in the column reactor under the HRT condition of 24 hours were Al 97.5%, As 98.8%, Cd 86.1%, Cu 96.2%, Fe 99.7%, Mn 64.1%, Pb 97.2%, Zn 66.7%, and $SO_4{^{2-}}$ 76.0% during 121 days of operation time. The XRD analysis showed that the ferric iron from AMD could be removed by adsorption and/or ion-exchange on the porous ZS ceramics. In addition it was known that Al, As, Cu, Mn, and Zn could adsorb or coprecipitate on the surface of Fe precipitates such as schwertmannite, ferrihydrite, or goethite. The EDS analysis revealed that Al, Fe, and Mn, which were of relatively high concentration in the AMD, would be adsorbed and/or ion-exchanged on the porous ZS ceramics and also exhibited that Al, Cu, Fe, Mn, and Zn could be precipitated as the form of metal hydroxide or sulfate and adsorbed or coprecipitated on the surface of Fe precipitates. The microscopic results on the porous ZS ceramics and precipitated sludge in a column reactor system suggested that the heavy metals and sulfate ion from AMD would be eliminated by the multiple mechanisms of coprecipitation, adsorption, ion-exchange as well as precipitation.

• Journal of the Korea Society of Computer and Information
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• v.27 no.1
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• pp.91-96
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• 2022

With the development of the cloud industry, various efforts are being made to improve resource efficiency and environmental continuity in software development and operation methods. However, in constructing a conventional structure of structural scheme, if the functionality is improved and added, it has a problem that the efficiency of full build arrangement is reduced for the changed source. In this paper, if a problem occurs in a solution service company, communication between the development department and the operation department can be facilitated and responded quickly, and the latest source updated during processing of the problem is the management system, provided is a system that can take advantage of CI tools and continuously integrate them. As communication through the proposed system is smooth, it is expected that unnecessary work can be reduced and the speed of development can be improved.

• Journal of Microbiology and Biotechnology
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• v.33 no.1
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• pp.96-105
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• 2023

Probiotic supplements have promising therapeutic effects on chronic diseases. In this study, we demonstrated the anti-obesity effects of two potential probiotics, Bifidobacterium bifidum DS0908 (DS0908) and Bifidobacterium longum DS0950 (DS0950). Treatment with DS0908 and DS0950 postbiotics significantly induced the expression of the brown adipocyte-specific markers UCP1, PPARγ, PGC1α, PRDM16 and beige adipocyte-specific markers CD137, FGF21, P2RX5, and COX2 in C3H10T1/2 mesenchymal stem cells (MSCs). In mice with high-fat diet (HFD)-induced obesity, both potential probiotics and postbiotics noticeably reduced body weight and epididymal fat accumulation without affecting food intake. DS0908 and DS0950 also improved insulin sensitivity and glucose use in mice with HFD-induced obesity. In addition, DS0908 and DS0950 improved the plasma lipid profile, proved by reduced triglyceride, low-density lipoprotein, and cholesterol levels. Furthermore, DS0908 and DS0950 improved mitochondrial respiratory function, confirmed by the high expression of oxidative phosphorylation proteins, during thermogenesis induction in the visceral and epididymal fat in mice with HFD-induced obesity. Notably, the physiological and metabolic changes were more significant after treatment with potential probiotic culture-supernatants than those with the bacterial pellet. Finally, gene knockdown and co-treatment with inhibitor-mediated mechanistic analyses showed that both DS0908 and DS0950 exerted anti-obesity-related effects via the PKA/p38 MAPK signaling activation in C3H10T1/2 MSCs. Our observations suggest that DS0908 and DS0950 could potentially alleviate obesity as dietary supplements.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.37-44
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• 2008

This study was performed to synthesize Na-A type zeolite with melting slag from the Mapo incineration site and recycle the zeolite as an environmental remediation agent. The melting slag used had a favorable composition containing 26.6% $SiO_2$, 10.9% $Al_2O_3$ and 2.7% $Na_2O$ for zeolite synthesis although there were high contents of iron oxides, including 19.6% $Fe_2O_3$ and 18.9% FeO, which had been used as a flux for the melting. It was confirmed that the Na-A type zeolite could be successfully synthesized at $80^{\circ}C$ and $SiO_2/Al_2O_3\;=\;0.80{\sim}1.96$. The cation exchange capacities (CEC) of the zeolites was determined to be about 220 cmol/kg leveled off at the synthetic time more than 10hrs. The adsorption capacities of zeolite to heavy metals (Cd, Cu, Mn and Pb) were high except for As arid Cr. It was also confirmed through the Eh and pH analysis that As and Cr existed in the forms of $HAsO_4^{2-}$ and $CrO_4^{2-}$. The low absorption rates of zeolite for As and Cr are attributed to the fact that the pore size ($4\;{\AA}$) of Na-A type is smaller than those of $HAsO_4^{2-}$ and $CrO_4^{2-}$ ions ($4\;{\AA}$ ionic radii and $8\;{\AA}$ diameter).

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.87-92
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• 2014

Purpose: Comparison with contrast sensitivity between binocular and monocular of 20s adult was measured by spatial frequency 3.0, 6.0, 12.0 and 18.0 cpd and compares difference between monocular and binocular and difference between male and female. Methods: Topcon CV-3000 Phoroptor was used for full correction of 99 ophthalmic optics students and contrast sensitivity were measured by using Vector Vision CSV-1000E at 2.5 m in photopic condition (100 $cd/m^2$). Results: Photopic condition at 2.5 m, average contrast sensitivity of entire subject was 52.54, 80.40, 36.79 and 13.56 with right eye and 52.33, 81.29, 41.73 and 14.22 with left eye in 3, 6, 12 and 18 cpd. For both eye 65.46, 113.69, 52.04 and 19.44 were measured. The contrast sensitivity of male was 58.22, 83.52, 37.89 and 13.82 with right eye and 56.03, 46.68 and 15.67 with left eye in spatial frequency of 3, 6, 12 and 18 cpd. Both eyes were measured to 70.89, 120.96, 56.56 and 19.89. The contrast sensitivity of female was 46.50, 77.09, 35.61 and 13.28 with left eye and 48.40, 70.43, 36.47 and 12.68 with left eye in spatial frequency of 3, 6, 12, 18 cpd. Both eyes were 59.68, 105.97, 47.23 and 18.95. Conclusions: Contrast sensitivity value of binocular shows higher than monocular to both male and female. Contrast sensitivity of difference between male and female were statistically remarkably higher to male in right eye 3 cpd, left eye 6 cpd, 12 cpd and both eye 3 cpd. In other frequency, there was no statistical significance but male shows higher.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.118-127
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• 2005

The best way to treat livestock manure is a recycling the manure to arable land as an organic fertilizer. In this study, fermented cow manure compost and pig manure compost were used as a raw materials for pelletizing. The changes of physicochemical properties of each composts and pellets were investigated. The aim of this research was to improve availability of livestock manure compost. In pelletizing process of fermented livestock manure compost, the optimal water content to make pellet was around 40%. When clay was mixed by volume more than 15% as a bonding agent, the condition of pelletizing process was beginning to improve. On a dry matter basis, the contents of N, P and K of fermented pig manure compost were 2.05%, 1.89% and 1.31%, respectively. After pelletizing, the contents of compost pelleted with the pig manure compost were 1.96% 1.73% and 0.89%, respectively. The same parameters of cow manure compost were 2.52%, 1.01% and 2.98%, respectively. After processing, the contents of compost pelleted with the cow manure compost were 2.45%, 1.10% and 2.93%, respectively. After pelletizing, there were little change in the content of heavy metals such as Pb, Cd, As and Hg. When pelleted compost dried naturally was submerged in water, it was completely dissolved in 30 minutes. On the other hand, Pelleted compost dried with the mechanical convection oven set $70^{\circ}C$ for 24 hours was completely dissolved in 960 minutes. The volume and weight of pelleted compost were decreased with time. After 30 days of storing, the weight of pelleted compost was decreased by 15% compared with its original weight. The volume of it was decreased by 17~25% in the same time.