• The Korean Journal of Soil Zoology
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• v.6 no.1_2
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• pp.11-16
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• 2001

This study was carried out to investigate the species composition and its abundance in the heap of compost, wild-grass, and sewer. 1,525 individuals were collected from 11th July, 2000 to 3rd August, 2000 at the 108 sites. They encompassed 3 families, 4 genera and 6-8 species. Species composition and its percentile abundance were as follows: Eisenia fetida 86.2%, Aporectodea trapezoides 0.5%, Amynthas hilgendorfi 1.1%, Amyntha agrestis 2.8%, A. koreanus group 6.3%, Drawida sp. 17%, Others 1.4fo in the compost heap, Eisenia fetida 9.8%, Aporectodea trapezoides 9.1%, Amynthas hilgendorfi 12.1%, Amyntha agrestis 25.1%, A. koreanus group 27.8%, Drawida sp 2.8%, Others 13.2% in the wild-grass and Eisenia fetida 24.2%, Aporectodea trapezoides 5.4%, Amynthas hilgendorfi 10.2%, Amyntha agrestis 5.4%, A. koreanus group 26.3%, Drawida sp 1.6%, Others 22.6% in the sewer.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.303-306
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• 2006

This experiment was investigated the influence of water stress in growth and yields of safflower. The water stress treatment was early growth stage(Mar. 20~Apr. 18), middle growth stage(Apr. 29~May 28) and last growth stage(Jun. 8~Jul. 7) for 30 days, respectively. Stem length of plant was 127 cm in normal irrigation(control) state and that of growth middle stage at drought state was 96 cm, to be shorted more 31 cm than that of normal irrigation state, also other growth rate of plant was decreased, relatively. Number of effective flower bud per $m^2$ was 224 ea in normal irrigation state, 114 ea in growth middle stage at drought state. Yield of seed at drought state decreased 37% and 13% in growth middle stage(222 kg/10a) and last stage(307 kg/10a) than 353 kg/10a in normal irrigation state. According to the result, it could be estimated that optimum irrigation time(0.05 MPa) was 23days after non-rainfall at early growth stage(from sowing seed time to 30 days after sowing seed), 10 days in middle growth stage(41-70 days after sowing seed) and 9 days in last growth stage(81-110 days after sowing seed), to prevent the damage of drought.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.245-249
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• 1986

A pot and laboratory experiments were conducted to find out the effects of pretreatments of rice straw and silica fertilizer in submerged and upland soil condition on the evolution of nitrous oxide with different application time. The results obtained were summarized as follows; 1. Evolution of nitrous oxide was remarkably increased with pretreatment of rice straw and silica in upland condition than that of submerged condition. 2. Effects of application time of rice straw and silica fertilizer on the evolution of nitrous oxide were high in order of two weeks before transplant > early spring (February) > late autumn (November) application. 3. The consumption ratio of carbon for the evolution of one mole nitrogen was pronounced more in submerged condition than that of pretreated in upland condition. Application of rice straw with silica fertilizer was remarkably reduced the consumpotion of carbon on the denitrification path way. 4. Amount of mineral nitrogen as $NH_4^+-N$, $NO_2^--N$, and $NO_3^--N$, and nitrification rate were remarkably high in pretreatment of rice straw and silica in upland condition than that of contineusly submerged soil condition.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.95-100
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• 1995

-양사면에서의 쇄파현상은 많은 연구에 의해 매우 선명하게 됐다. 그러나, 실제의 해저지형은 연안사주가 존재하는 복합단면지형의 경우가 많고, 이러한 지형에서의 쇄파현상은 충분히 해명되어 있지 않다. 본 연구에서는 복합단면에서의 쇄파감쇠과정을 검토하는 기초적지형으로써 사면에 연접한 수평상을 선택하여 검토하도록 한다. 이러한 지형을 여기서는 수평step이라고 한다. 수평step상을 대상으로 하는 기존의 연구로써 굴천·곽(1966), 수구(1978)등을 들 수 있다. (중략)

• Journal of Korean Society of Forest Science
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• v.107 no.3
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• pp.278-286
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• 2018

This study examined the damage characteristics through investigation for a total of 10 factors (longitudinal position, crossing position, soil type, collecting well volume, outlet position, water apron material, waterway existence, pipe culvert diameter, pipe culvert gradient, pipe culvert height) affecting outlet damages of forest road cross drainage for forest roads in the Research Forest of Kangwon National University. We predicted outlet damages of forest road cross drainage for forest roads using a discriminant analysis Results showed that longitudinal position, crossing position, soil type and pipe culvert height did not affect damages caused to forest road cross drainage. Most influential factors affecting outlet damages were outlet position, waterway existence, pipe culvert diameter, pipe culvert gradient and collecting well volume, respectively. The discriminant ratio calculated from the developed discriminant function was 68.8% which is reasonably reliable.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.45-49
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• 2000

Tolerances of aquatic plants (emergent plants) of cattail (Typha orientalis), water oats (Zizania latifolia), reed (Phragmites communis), and bulrush (Scirpus nipponicus) to salts and high NH₄/sup ＋/-N cone. of industrial wastewater were evaluated. Evapotranspiration of cattail and water oats plants was not affected when the wastewater containing 130 ppm NH₄/sup ＋/-N with electrical conductivity of 3.0 dS/m was supplied for 5 months. Shoot and root dry wt. of cattail and water oats were rather increased by irrigation of the wastewater while the biomass production of bulrush was greatly reduced. Storage nitrogen concentration in tissues of water oats and reed plants were higher than those in cattail and bulrush. Thus, water oats and reed plants were found to be the better aquatic plants to use in constructed wetlands for treating industrial wastewater of high salt and NH₄/sup ＋/-N.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.3
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• pp.294-301
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• 1987

This experiment was carried out to investigate the occurrence of tiller and its proportion to grain yield under 5 different plant densities. Plant density 5 x 5cm was more favorable for increasing the number of spikes per unit area, where leads to improve grain yield. Effective tillers showed only main stem, M$_1$-axil and M$_2$-axil, indication more effective tillers in M$_1$ rather than main stem. Every tillers held at least 6 leaves to bear spikes, indicating that main stem has 12 -13 leaves. Leaves attached on main stem M$\sub$0/ and M$_1$ were very important as main source of photosynthesis, especially under more compart plant densities while leaves of M$_1$ occupied 66.8% in a plant. The proportion of grain yield of each tiller to total grain yield per plant was high in main stem under conpact plant density, in M$_1$ stems under less compact plant density, and in M$_2$ -stems under wide plant density, indicating same result on multiple regression analysis.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.1-8
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• 2003

Two types of ground-water sampling techniques for CFCs (chlorofluorocarbons) analysis, the cold-welded copper tube method and flame-sealed borosilicate glass ampule method, were compared and evaluated. CFCs concentrations by the copper tube method showed a poor reproducibility among triplicates whereas those by the glass ampule method showed a good agreement and relative standard deviations of triplicates were less than 5%. The poor reproducibility of the copper tube method appears to be attributed to the incomplete sealing in connection between faucets of wellhead and the sampling apparatus. The copper tube method also showed higher CFCs concentrations than the glass ampule method, which is more pronounced for CFC-11 than for CFC-12. The plastic tubings and rubber gasket of faucets in case of the copper tube method possibly contaminated the samples with CFC-11 and CFC-12. The potential of CFCs contamination for the glass ampule method was eliminated by using stainless steel and Nylon only and by connecting the sampling equipment directly to the main discharge pipe of wellhead. The validity of the glass ampule method were also verified by detecting very low level of CFCs for the ground-water sample which is old enough to have negligible CFCs.

• The Journal of the Korea Contents Association
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• v.12 no.2
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• pp.339-348
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• 2012

Acute promyelocytic leukemia (APL) is a cancer of the blood and bone marrow. Although all-trans retionic acid (ATRA) is the agents for ALP therapy, there are various side effects. For overcome this problem, we need the development of new therapeutic agents for APL. A number of bacteria produce various virulence factors with cytotoxic effects on human cancer cells. To understand the anti-cancer effect of Listeria monocytogenes on APL, we examined alteration of the cell viability, apoptosis and cell cycle arrest of the human promyelocytic leukemia cell line, HL-60 cells. The cell supernatant (LmSup) and the extract of L. monocytogenes (LmE) inhibited the cell viability and induced apoptosis of HL-60 cells. These cytotoxic effect of LmSup and LmE mediated by modulation of cell cycle and ROS production. These results indicate that released or included bacterial molecules from L. monocytogenes have a cytotoxicity in HL-60 cells. Therefore, LmSup and LmE may be used as the potential target for the treatment of cancer induced by HL-60 cells.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1051-1061
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• 2011

The influences of density variation on stress and displacement fields at a propagating Mode-III crack tip in orthotropic functionally graded materials (OFGMs) are studied. The crack propagates dynamically at a right angle to the gradient of physical properties. Three kinds of elasticity and density gradients are analyzed in this study. They are as follows: (1) the density varies without elasticity variation, (2) the directions of the density and elasticity gradients are opposite to each other, and (3) same. For these cases, the stress and displacement fields at the crack tip are developed and the dynamic stress intensity factors for propagating cracks are also studied. When the crack speed is low, the influence of density variation on the stresses and displacement is low. However, when the crack speed is high, this influence is very high.