• Electrical & Electronic Materials
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• v.5 no.2
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• pp.189-197
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• 1992

고온 초전도체 $Y_{1}$Ba$_{2}$Cu$_{3}$O$_{7-y}$에서 Y를 Sm으로 치환시켰을 때의 자기 임계 전류밀도와 저항은 각각 30K와 80-160K의 온도에서 측정되었다. 그리고 X-선 회절분석 및 적외선 투과율 측정은 실온에서 수행되었으며 시료들은 고상 반응법에 의해서 제조되었다. 93K근에의 값을 갖는 초전도 전이온도 T$_{c}$는 치환양에 따라 거의 변하지 않았다. 시료들의 결정구조는 X-선 회절무늬로 부터 모두 직방정계임이 판명되었다. 적외선 투과율 측정에서 날카로운 peak들은 472.78-618.53$cm^{-1}$ /범위에 있었다. 이것은 특이할 정도로의 low-lying plasmalike edge와 낮은 에너지의 전자적인 여기가 존재함을 나타내는 것이다. 자기 임계 전류밀도는 $10^{3}$~$10^{4}$A/$cm^{2}$범위에 있었다. 전이온도 T$_{c}$에 상자성 불순물의 영향이 거의 없는 것으로 보아 123phase에서 Y가 고온 초전도성에 주된 역할을 하지 않음을 알수 있었다.다.

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.95-100
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• 2018

The purpose of this study was to investigate the effects of cognitive programs on cognitive function improvement in patients with mild dementia. The subjects were 30 patients with mild dementia. The subjects were applied the cognitive rehabilitation program three times a week for 6 weeks and analyzed the pre-experiment and post-experiment values through the Korean simplified mental state examination (MMSE-K). The results were as follows: The mean of test was increased and statistically significant. Thus, cognitive rehabilitation programs for patients with mild dementia are effective interventions to improve cognitive function in patients with dementia.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.4 s.56
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• pp.148-158
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• 2009

Firstly the problems of existing foreign code concerning wheel load distribution factor for skew box girder bridges have been examined, and the main parameters which have effects on wheel load distribution factors are evaluated in this study. Further finite element analyses on various skew steel box girder bridges are carried out. Based on the analysis results, formulas to determine wheel load distribution factors are proposed using multiple regression analysis. It is found when using the proposed formulas in this study weak points of existing specifications could be improved and also time spent at structural analysis should be saved a lot, so that the validity and practicality could be verified.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.592-599
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• 1996

The variations of asparagine and aspartic acid contents among the soybean varieties and in the different parts of soybean sprout after the different durations of storage were investigated. Asparagine and aspartic acid are known to have the detoxifying effects on acetaldehyde, which is highly toxic metabolites in the process of alcohol metabolism in the human body. The contents of asparagine and aspartic acid of beansprout showed continuosuly increasing trends along with the days to cultivation with a great varietal difference, especially in the roots. The duration of seed storage did not affect contents of asparagine content; the longer storage decreased aspartic acid content remarkably.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.73-78
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• 2005

This work was carried out to investigate the antioxidative effects of Acanthopnax sessiliflorus from Jeongseon County for the purpose of development of a novel antioxidant from natural products. The antioxidant activity was determined by using electron paramagnetic resonance (EPR), not measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) which have bun used for antioxidant activity of natural sources. Although DPPH radical scavenging activity assay have been generally used for antioxidant activity, this assay is nut appropriated for determinating which radical is scavenged by extracts from natural products. Using EPR, we determinated whether A. sessiliflorus extracts from Jeongseon County scavenge specific radicals or not. On experiment of scavenging superoxide anion radical, hydroxyl radical, nitrogen dioxide and peroxinitrite. Extracts from A. sessiliflorus showed high antioxidant activities to reactive oxygen and nitrogen species. These result suggest that extracts from A. sessiliflorus act as an antioxidant by scavenging reactive oxygen and nitrogen species and used as new cosmetic ingredients for anti-oxidative stress in skin.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.313-324
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• 2009

We explore the effect of particle shape and size on 3-dimensional (3D) network and pore structure of porous earth materials composed of glass beads and silica gel using NMR micro-imaging in order to gain better insights into relationship between structure and the corresponding hydrologic and seismological properties. The 3D micro-imaging data for the model porous networks show that the specific surface area, porosity, and permeability range from 2.5 to $9.6\;mm^2/mm^3$, from 0.21 to 0.38, and from 11.6 to 892.3 D (Darcy), respectively, which are typical values for unconsolidated sands. The relationships among specific surface area, porosity, and permeability of the porous media are relatively well explained with the Kozeny equation. Cube counting fractal dimension analysis shows that fractal dimension increases from ~2.5－2.6 to 3.0 with increasing specific surface area from 2.5 to $9.6\;mm^2/mm^3$, with the data also suggesting the effect of porosity. Specific surface area, porosity, permeability, and cube counting fractal dimension for the natural mongolian sandstone are $0.33\;mm^2/mm^3$, 0.017, 30.9 mD, and 1.59, respectively. The current results highlight that NMR micro-imaging, together with detailed statistical analyses can be useful to characterize 3D pore structures of various porous earth materials and be potentially effective in accounting for transport properties and seismic wave velocity and attenuation of diverse porous media in earth crust and interiors.

• Fire Science and Engineering
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• v.30 no.1
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• pp.43-48
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• 2016

In this study, the experiment to confirm the risks of particulate material was carried out as a precedent study for developing the toxicity evaluation method of combustion products including the toxicity of particulate material. In the experiment, the test result of filtering and exposing particulate material among combustion products and that of exposing combustion products including particulate material were compared and analyzed by analyzing changes in average movement stop time according to the installation of Membrane filter between the stirring box and test box through the gas toxicity test of the same specimen to filter particulate material among combustion products. As the test result, in case of installing a filter, the average movement stop time of an experimental rat increased by up to 264% in case of lumber specimen and up to 179% in case of urethane specimen. Through such result, the necessity of identifying the toxicity of particulate material and carrying out quantitative toxicity test for particulate material was confirmed.

• Journal of the Korean Magnetics Society
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• v.8 no.4
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• pp.192-197
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• 1998

The Mossbauer spectra of the $Ni_{1-x}Cd_xFeAlO_4$ system were investigated with the Cd content x at room temperature. The spectra of the samples exhibit various patterns as follows 1) superparmagnetic relaxation for 0$\leq$x$\leq$0.2, 2) ferrimagnetic sextet for 0.3$\leq$x$\leq$0.5, 3) ferromagnetic relaxation for x=0.6, 0.7, 4) paramagnetic doublet for 0.8$\leq$x$\leq$1, with the Cd content x. In the samples with x values from 0 to 0.2, the substituted $Cd^{2+}$ ions transfer the $Al^{3+}$ ions from A-site to B-site mainly. The superparamagnetic relaxation effect and the ferromagnetic relaxation effect are derived from the $Al^{3+}$, $Cd^{2+}$ respectively. The magnetic structure of the $Ni_{1-x}Cd_xFeAlO_4$ system was explained by the Yafet-Kittel model.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.09a
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• pp.98-99
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• 2001

• The Korean Journal of Applied Statistics
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• v.15 no.2
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• pp.433-448
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• 2002

Revelation is emphasized in exploratory data analysis. Hence, many graphical techniques are used in exploratory data analysis. Three applications of graphs in exploratory data analysis are presented.