• Journal of Industrial Technology
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• v.21 no.A
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• pp.317-327
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• 2001

For soils with high void ratios, the inverse method of utilizing results obtained from centrifuge model test was used to find the constitutive relation of effective stress - void ratio - permeability whereas conventional oedometer test and constant rate of strain consolidation test were also used to fine its relation at ranges of relatively low void ratio. Results of column test about settlement of interface and pore pressure and distribution with time were compared with numerically estimated values to confirm such a constitutive relation as obtained from the inverse method. Consolidational settlement in dredged and reclaimed ground, where the consolidation was in progress, was predicted by using the numerical technique implemented with the finite strain consolidation theory.

• Journal of Microbiology
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• v.39 no.4
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• pp.326-330
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• 2001

Mycobacterium sp. C2-3 was isolated from petroleum contaminated soil around an oil reservoir and identified by analysis of its 16S rRNA gene sequence, Strain C2-3 was able to use fluorene, phenan-threne, fluorathene and pyene as sole sources of carbon and energy, yet unable to geagrade naph-thalene, The strain was also able to use n-alkanes, such as hexadecane and heptadecane, and phenanthrene and pyrene, in particular, were degraded rapidly,. The phylogenetic data suggested that the isolate C2-3 is a thermosensitive, fast-growin strain of Mycobacterium sp.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.2
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• pp.64-72
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• 1995

A series of cubical triaxial tests with three independent principal stresses was per- formed on Baekma river sand( # 40~100). It was found that the major principal strain at failure remained approximately constant for b values larger than about 0.3 for both the drained and undrained condition, and thereafter increased as b value decreased. The test results showed that the direction of the strain increment at failure form acute angles with the failure surfaces for both the drained and undrained condition. The results were thus not in agreement with the normality condition from classic plasticity theory. Howev- er, it was found that the projections of the plastic strain increment vectors on the octahe- dral plane were perpendicular to the failure surface in that plane. Failure strength in terms of effective stress anlaysis was greatly influenced by the variation of intermediate principal stress and so was failure criterion. The effective stress failure surfaces for both the drained and undrained condition were estimated quite well by use of Lade's failure criterion.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.397-401
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• 1996

A bacterial strain CFCl, which produced an extracellular cycloinulooligosaccharide fructanotransferase(CFTase), was isolated from soil. The isolated strain was identified as a strain of Bacillus sp. The synthesis of CFTase by the bacterium was found to be induced by inulin which was added to the culture medium as a carbon source. The highest activity of CFTase was observed at pH 7.5 and $37^{\circ}C$ in the medium containing 4% inulin and 0.5% peptone as a carbon source and a nitrogen source, respectively. Under the optimal conditions, the enzyme activity in the culture supernatant reached the highest level of 85 munits/ml after 96 h cultivation.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.445-451
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• 1996

The strain YCH-37, which produces yeast cell wall lytlc enzyme, was isolated from soil. From the microscopic observation, morphological and cultural characteristics, this strain was identified to fungus, Dicyma sp. So, we named this strain as Dicyma sp. YCH-37. The lytic enzyme effectively lysed Salmonella typhimurium among intact living bacteria and Torulopsis, Hansenula, Zygosaccharomyces among intact living yeast, as well as autoclaved yeast strains. The yeast cell wall lytic enzyme was succesively purified to 204 folds with 13% yields through yeast glucan affinity adsorption and DEAE-cellulose column chromatography. The enzyme was identified to monomeric protein with molecular weight of 25,000 daltons from the results of SDS-PAGE and gel filtration. The optimum pH and temperature for the yeast lytic activity were 8.0 and 50$\circ$C, respectively. The enzyme was stable up to 40$\circ$C, and between pH 4.0-pH 10.0.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1490-1494
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• 2014

To probe the genomic properties of microbes thriving in desert lakes, we sequenced the full genome of a betaproteobacterial strain (SL110) belonging to the understudied genus Caenimonas of the family Comamonadaceae. This strain was isolated from a freshwater lake in the western Gobi Desert, Northern China. Its genome contains genes encoding carbon monoxide dehydrogenase, nitrate reductase, nitrite reductase, nitric oxide reductase, and sulfur oxidation enzymes, highlighting the potentially important contribution of this group of bacteria to the cycling of inorganic elements in nature. Unexpectedly, a coenzyme $F_{420}$ biosynthesis gene cluster was identified. A further search for $F_{420}$ biosynthesis gene homologs in genomic databases suggests the possible widespread presence of $F_{420}$ biosynthesis gene clusters in proteobacterial genomes.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1144-1156
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• 2008

In this paper, heaving phenomenon is analyzed by laboratory tests. A laboratory test is consist of building soft clay foundation in plane-strain soil tank, construction of retaining wall, and excavation work. And range of shear strain, and destruction shape about soft clay foundation is compared, and analyzed with results of proposal formula. Using this study, safety factor is suggested for heaving phenomenon in the construction of wall on the soft clay. Actual theory is suggested by this suggested safety factor. There are various proposal formula for heaving phenomenon. For example, Terzaghi & Peck, Tschebotarioff, Bjerrum & Eide(Experience formula) and so on. Terzaghi & Peck's proposal formula is chosen, compared with laboratory test's result and analyzed in this study. A soft clay used in study is assumed homogeneous. A Depth of foundation is enough to observe shear strain by heaving phenomenon. Retaining wall is enough hard not to have vertical displacement.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.219-222
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• 2000

To produce and utilize microbial cyclomaltodextrinase being industrially useful, we isolated an alkalophilic Bacillus strain from soil which was capable of degrading cyclodextrins. The newly isolated strain was aerobic, gram-positive, spore-forming, motile, rod shape(0.2~0.4$\times$1.4~4.4 $\mu\textrm{m}$), and 35.8 mol% of DNA base composition. Based on its morphological, phisiological, and biochemical properties, it was identified as alkalophilic Bacillus sp. KJ-133 and cultivated well in the ranges of $30~40^{\circ}C$ and pH 8.0~9.0 . The cyclomaltodextrinase of the strain showed maximal production after 48h of cultivation at $37^{\circ}C$, and the activity was inhibited by Ag2+, Hg2+, Cu2+, and p-chloromercuribenzoate.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.880-884
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• 2008

A strain of Streptomyces sp. (M10) antagonistic to Botrytis cinerea was isolated from orchard soil obtained from Jeju Island, Korea. An antifungal substance (CN1) was purified from the culture extracts of the strain, and then identified as valinomycin through extensive spectroscopic analyses. Valinomycin showed potent in vitro antifungal activity against Botrytis cinerea and also in vivo control efficacy against Botrytis blight development in cucumber plants. Overall, the disease control efficacy of valinomycin was similar to that of vinclozolin, a commercial fungicide. This study provides the first report on the disease control efficacy of valinomycin against Botrytis blight.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.273-276
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• 2008

Equivalent linear method indirectly reflects a variation of shear modulus(G/Gmax) and damping ratio $(\xi)$ by selects mean value of every response analysis. Existing equivalent linear method does not properly consider variation of shear strain along frequencies and uses mean value. Real dynamic soil behavior is affected by shear stiffness and damping ratio. Modified equivalent linear method is developed to consider variation. Modified equivalent linear method can reflects high strain at low frequency and low strain at high frequency by using an easement curve. This study presents propriety of method by case study.