• Journal of Life Science
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• v.9 no.3
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• pp.314-327
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• 1999

This study was investigated to isolate identify the total bacteria and fungi from the indoor air of work-place of the shoes, paint, stainless steel, and plastic industries. The number of bacterial colonies on the nutrient agar plates were calculated by the open petridish method for 30 minutes in indoor air of work-places at the autumn and winter. The isolated bacteria were identified by Gram stain and biochemical test using API Staph and API 20E kits. The isolated fungal colonies were identified by gross appearance of the giant colonies and microscopic examination of their spore and hyphal characteristics on the slide culture method. The minimum inhibitory concentration (MIC) of several antibiotics against isolated bacteria was determined by the microdilution method with Mueller-Hinton broth. The 70-400 colonies in autumn and 54-236 colonies in winter were isolated from the indoor air of work-places of several industry. The isolation rates of Gram positive cocci, Gram positive bacilli, Gram negative bacilli, and Gram negative cocci were 46.3%, 19.8%, 17.3%, and 16.1%, respectively. In Gram positive cocci, the most strains were identified as Aerococcus spp, Micrococcus spp, and Staphylococcus spp. In Gram positive and negative bacilli, and Gram negative cocci were identified as Bacillus spp, Pseudomonas spp, and Neisseria spp, respectively. The frequently isolated fungi were Aspergillus spp, Penicillium spp and Rhizopus spp, respectively. The frequently isolated Aerococcus spp, Micrococcus spp, and Staphylococus spp were highly resistance against ampicillin, erythromycin, methicillin, and tetracycline. These results arouse our attention to microbiologic pollution in the indoor air of work-places of industries.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1141-1146
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• 2010

Isolated the heterotrophic aerobic bacteria in sandfiltered water on NA and TSBA solid medium, selected 8 dominant species and identified by Sherlock System. Each samples are irradiated 0, 5, 16, 40 and $60\;mJ/cm^2$ using on CBD (Collimated Beam Device) Medium Pressure UV lamp after these identified bacterium did liquid culture how to make $10^6{\sim}10^7\;cells/mL$ suspended in dilution water. Then cultured bacteria are estimated inactivation rate on plate media. Identified Gram positive group are Bacillus Subtilus, Bacillus megaterium, Rhodococcus erythropolis and Microbacterium laevaniformans; Gram negative group are Pseudomonas vesicularis, Pseudomonas pseudoflava, Alcaligenes paradoxus and Zooglea ramigera. These isolation of bacterium are more stronger reference strain and high resistance of MP UV irradiation, Besides Gram negative bacterium are more sensitive Gram positive bacterium on MP UV dose. Now we are estimating to $60{\sim}100\;mJ/cm^2$ MP UV dose for efficient disinfection in water treatment plant.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.4
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• pp.719-725
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• 2011

To apply TMAH-based Py-MS to a field biological detection system for real-time classification of cell-type, reproducible patterns of the TMAH-based Py-MS spectra was known as a critical factor for classification but was seriously disturbed by quantity of cells injected into pyro-tube. This factor is an exterior variable that could not be complemented by improving the performance of the TMAH-based Py-MS instrument. One of idea to solve the knotty problem has been flashed from "Top-down proteomics for identification of intact microoganisms". That is, biomarker peaks are selected from complicate Py-MS spectra for intact microoganisms by tracing out their origins, based on Py-MS spectra for the featured components of different cell-types, in Top-down approach. This idea has been tested in classification of different Gram-type microoganisms. Through the analyses of spectra for the featured components - peptidoglycan and lipoteichoic acid for Gram-positive cells and lipopolysaccharide and lipid A for Gram-negative cells - with comparing to the spectra the corresponding Gram-type cells in the Top-down approach, biomarker peaks were selected to carry out PCA(Principal Component Analysis) in order to see classification of different Gram-types, resulting in significant improvement of their classification. Furthermore, weighting biomarker peaks on intact cell's spectra, based on the data for the featured components of the Gram-types, contributed to elevate classification performance.

• Tunnel and Underground Space
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• v.22 no.6
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• pp.373-382
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• 2012

Cessation of dewatering usually results in groundwater rebound after closing an underground coal mine because the mine voids and surrounding strata flood up to the levels of decant points such as shafts and drifts. Several numerical models have been developed to predict the timing, magnitude and location of discharges resulting from groundwater rebound. This study reviews the numerical models such as VSS-NET, GRAM and MODFLOW, and compares their scopes of assessment at different spatial and time scales. In particular, the GRAM model was reviewed in details to implement it. This paper describes the implementation of GRAM model and its application to the Dongwon coal mine in Korea. The application showed that the groundwater level modeled at the shaft of Dongwon coal mine using the GRAM model is similar to the observed one in the field.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1038-1044
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• 1997

The mode of the combined effect of adipic acid and medium chain monoglycerides was investigated by using nine strain. Though monoglycerides alone had little antibacterial activity against gram negative strains, the combined use with adipic acid showed much higher activity against others of gram positive strains as well as gram negative strains. But exceptionally, it seemed difficult practically to prevent the growth of lactic acid bacteria completely by the combined use of adipic acid and monoglyceride. For yeast and mold, monoglycerides alone had a high activity but adipic acid had a little activity. In antibacterial mechanism, we thought that adipic acid acted on the cell envelope and then monoglyceride acted on the altered cell.

• KSBB Journal
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• v.15 no.6
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• pp.594-599
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• 2000

The adsorption of the antimicrobial agents and their heat-resistance were investigated for the packaging film manufacture, wherein, the antimicrobial agents were adsorbed on a ceramic component. The naturally sourced antimicrobial agents were produced by methylotropic actinomycetes strains MO-16 and MO-17, extracted with ethylacetate. Antimicrobial action was stable to $121^{\circ}C$ and 1 atm. for 30 min., showing wide-ranging activity to the Gram(+) and the Gram(-) bacteria. Antimicrobial agents, adsorbed on ceramic Ce-1, retained activity to the Gram(+) and the Gram(-) species at $105^{\circ}C$ and $230^{\circ}C$ heat treatment, and methanol extracted antimicrobial agents from Ce-1 treated at $230^{\circ}C$ for 30min., retained activity to Gram(+) bacteria. In the presence of oxygen during the heat treatment process, antimicrobial agents adsorbed on ceramic Ce-1 showed antimicrobial activity to Gram(+) and the Gram(-) bacteria.

• Nuclear Engineering and Technology
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• v.7 no.1
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• pp.15-23
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• 1975

In the ,present study, recovery behaviour of cold compressed pure zirconium was investigated by the measurement of X-ray line breadth and microhardness. By isochronal annealing, it was found that both hardness and X-ray line breadth do not show remarkable decrease below 300"e. It was also found that at the same degree of cold work, the rate of recovery of X-ray line breadth is different from that of hardness, and that regardless of cold working degrees, activation energy for the recovery of X-ray line breadth is less than that of hard ness. Activation energies for recovery of X-ray line breadth in 8%, 19% and 28% cold worked zirconium were 64,800 cal/gram atom, 56,400 cal/gram atom and 48,500 cal/gram atom, respectively, and those of hardness were 72,800 cal/ gram atom, 64,300 ca1/9ram atom and 58,600 ca119ram atom, respectively.vely.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.402-404
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• 1998

최근 영상 정보를 저장하는 시스템의 급증으로, 영상의 특징 요소들의 유사성(similarity)에 근거하여 영상을 분류.검색하는 기술에 많은 관심을 보이고 있다. 본 논문에서는 칼라영상의 분류를 위해 기존의 N$\times$M-grams를 변형한 Color N$\times$M-grams를 제안한다. Color N$\times$M-grams는 영상의 칼라정보를 이용하여 영상고유의 구조 정보를 추출한 후 유사성을 측정하여 영상을 분류한다. 제안된 방법의 성능 평가를 위하여 39쌍의 Benchmark 영상을 사용하여 실험하였다. 실험결과, 제안한 Color N$\times$M-grams를 사용한 방법이 기존의 N$\times$M-grams를 사용하여 칼라 영상을 분류하는 방법보다 1순위로 분류되는 비율에 있어서 약 19% 더 좋은 결과를 보였다.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.60-66
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• 1988

Dynamics of bacterial communities and its colonization under aerobic gemp retting were observed in air lift fermentor as a closed system, unlike conventional hemp retting as an open system. Dried hemp which was harvested in both 1986 and 1987 was retted at room temperature. Predominant community was facultatively anaerobic Gram-negative rods, and its density was increased from $3.0\times 10^{7}$ cells/ml to $9.0\times 10^{8}$ cells/ml. The density of facultatively nanerobic Gram-positive fods was maintained at the lovel of $5.0\times 10^{6}$ cells/m, and this Gram-positive bacterial community was not participated in retting. In the Gram-negative bacterial community during the retting, five types of colonieswere developed at early stage of pH7.0-8.0, and thereafter, only three types were colonized till later stage, shich were identified as pectolytic strain Erwinia salicis, Erwinia tracheiphila and Enterobacter agglomerans. A community of facultatively Gram-negative rods was mainly proliferated in stems and dispersed into liquor after 6-8 hours. Retting was terminated within 70-80 hours.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1295-1300
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• 2007

The antibacterial effects of anodic electrolyzed water against various bacteria were studied in this investigation. Complete inactivation of Gram-positive and Gram-negative bacteria occurred within 15 s after exposure to anodic electrolyzed water. Moreover, 1/2, 1/5 and 1/10 diluted anodic electrolyzed water by adding deionized water showed strong antibacterial effects. However, the inhibitory effect of anodic electrolyzed water on the anaerobe of Propionibacterium acnes was much weaker than that on the aerobes, including Gram-positive and Gram-negative bacteria. The degraded fragments of E. coli cell were observed upon treating anodic electrolyzed water for 1 min by using scanning electron microscopy.