• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.31-37
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• 2003

The expanded uncertainties calculated by the application of GUM -approximation and Monte-Carlo simulation were compared about the model equation of one-point calibration which is widely used for the measurements and chemical analysis. For the comparisons, we assumed a set of artificial data at the various level of concentration and dispersion of t or normal distribution. Mistakes of more then 50 % was revealed at the values calculated by GUM-approximation in comparison with those of Monte-Carlo simulation because of the excess dispersion from t-distribution and non-linearity by division in the equation. In contrary, the mistake of calculation due to non-linearity of the equation was not observed in the level of detection limits with the equation of one-point calibration, because of the relatively large values of uncertainty in response.

• Polymer(Korea)
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• v.36 no.4
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• pp.507-512
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• 2012

Thin (~650 nm) and ultrathin (~50 nm) films of neat PMMA and PMMA containing 5 wt% of methacryl-polyhedral oligomeric silsesquioxane were prepared in this work. The effects of film thickness and POSS on glass transition temperature ($T_g$) and isothermal physical aging were investigated by means of differential scanning calorimetry (DSC). $T_g$ depression was observed as film thickness was decreased and Ma-POSS molecules were incorporated. Enthalpy relaxation (${\Delta}H_{Relax}$) due to the isothermal physical aging was reduced by ultra-thin film thickness and the addition of Ma-POSS. KWW (Kohlrausch-Williams-Watts) equation was used to fit ${\Delta}H_{Relax}$ vs. aging time data providing the fitting parameters; maximum enthalpy recovery (${\Delta}H_{\infty}$), relaxation time (${\tau}$) and non-exponentiality parameter (${\beta}$).

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.38-47
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• 2020

This study is designed as a one group pretest-posttest design the practice to investigate the effects of convergence cadaver practice on nursing professionalism and major satisfaction of nursing students. The participants were 133 nursing students who were in the anatomy course of M college from October 1 to October 30, 2018. The nursing professionalism resulted in changes from 3.50±.87 before the convergence cadaver practice to 3.44±.98 (t=.98, p<.330) after the convergence cadaver practice, and major satisfaction changed from 3.83±.81 before the convergence cadaver practice to 3.91±.78 (t=-.95, p<.345) after the convergence cadaver practice. The correlation between nursing professionalism and major satisfaction showed a positive correlation (r=.54, p>.001). Partial results of sub-areas showed increase, however, future studies that aim to develop and investigate the effects of specific convergence education program which includes cadaver practice to enhance qualitative structure of specialized foundation knowledge are needed.

• The Korean Journal of Zoology
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• v.28 no.1
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• pp.21-30
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• 1985

By two-dimensional gel electrophoresis loss of a cell-specific protein was detected in tD strain of Amoeba proteus that had been infected by symbiotic bacteria extracted from xD strain. In 50 days of experimental infection by induced phagocytosis the host amoeba lost the ability to synthesize the tD cell-specific protein even after removal of the infective bacteria and xD cell-specific protein by growing the amoebae at $27^\\circC$. By this time the host amoebae were obligately dependent on the bacteria. From these and other results (Lorch and Jeon, Science 221:549), it is clear that the incompatibility of the infected nuclei with the cytoplasm of the uninfected amoeba and the obligate dependence of the host on bacteria are due to the irreversible inactivation or the loss of the cell-specific gene by bacterial infection in this amoeba.

• Journal of the Korean Magnetics Society
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• v.9 no.2
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• pp.98-103
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• 1999

We have studied changes of coercivity $(H_c)$, exchange anisotropy field $(H_{ex})$ and MR ration in glass/Ta/NiFeI/CoI(t)/Cu/CoII(3/4 t)/NiFeII/FeMn spin valve structures by changing Ar pressure and thicknesses of Co layers using DC, RF sputtering methods. We obtained minimum coercivity of 2.8 Oe at 4 mTorr of Ar pressure, exchange anisotropy field of 50.0 Oe at 6 mTorr and 5.3 % of MR ratio at 10 mTorr. Also, we obtained 3.0 Oe of coercivity at 40 $\AA$ of CoI layer, 65.9 Oe at 13 $\AA$ and 4.7 % of MR ratio at 27 $\AA$ and 34 $\AA$ by changing the thicknesses of Co layers.

• Journal of Korean Society of Steel Construction
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• v.20 no.4
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• pp.561-570
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• 2008

The primary object of the paper is to identify the compression forces and inelastic failure behavior using steel plate-concrete structures. The compression tests were carried out for the three types of B/tratios by 25, 33 and 50. The tests proved that the compressive strength of the SC structures can be estimated by the summation of strengths both of the steel plate and concrete. The buckling of the steel plates had been occurring at the plates between studs. The empirical estimation of compressive strength for unstiffened SC structures under compressive loadings was suggested. The buckling behavior was also compared with the results of the finite element analysis.

• Journal of Korean Society of Steel Construction
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• v.20 no.4
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• pp.549-559
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• 2008

The objective of this paper is to identify the compression forces and inelastic failure mode using stiffened steel plate-concrete structures. The compression tests were carried out for the three types of B/t ratios by 25, 33 and 50. The test results proved that the compressive strength of the stiffened SC structures can be estimated by the summation of the strengths both stiffened steel plate and concrete. The buckling of the steel plates had been occurred at the plates between studs. The empirical estimation of compressive strength for the stiffened SC structures under compressive loadings was suggested. The buckling behavior also compared with the results of the finite element analysis. The good agreement has been achieved between the experimental results and finite element results.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.1
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• pp.144-150
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• 2001

The cytotoxic activity of Cratalariae sessiliflorae on cultured NIH 3T3 fibroblasts and human oral epithelioid carcinoma cells (KB) were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) colorimetric method These fractions of methanol extract of Cratalariae sessiliflorae showed inhibitory effect in vitro in the milligram range against KB cell lines. In general, the antitumor activities of these fractions were does-dependent over the milligram range. The comparison of IC50 values of these fractions in tumor cell lines showed that their susceptibility to these fractions decrease in the following order: Fr. 4> Fr. 6> Fr. 10> Fr. 2> Fr. 11> Fr. 3> Fr. 8> Fr. 7> Fr. 9> Fr. 1> Fr. 5 by the MTT assay. These fractions were tested for their cytotoxic effects on NIH 3T3 fibroblasts using MTT assay. They exhibited potent cytotoxic activities in vitro in the milligram range against NIH 3T3 fibroblasts. In general, the cytotoxic activities of these fractions were does-dependent over the milligram range. The comparison of CD50 values of these fractions in NIH 313 fibroblasts shows that their susceptibility to these fractions in decrease the following order: Fr. 10> Fr. 9> Fr. 2 = Fr. 4> Fr. 8> Fr. 11> Fr. 1 = Fr. 7> Fr. 3> Fr. 5 = Fr. 6 by the MTT assay. These results suggests that fraction 5 has the most growth - inhibitory activity against KB cell lines.

• Biomolecules & Therapeutics
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• v.25 no.3
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• pp.329-336
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• 2017

Adipogenesis in murine preadipocyte 3T3L-1 has been used as a model system to study anti-obese bioactive molecules. During adipogenesis in 3T3-L1 preadipocytes, we found that capsanthin inhibited adipogenesis ($IC_{50}$; $2.5{\mu}M$) and also showed lipolytic activity in differentiated adipocytes from the preadipocytes ($ED_{50}$; 872 nM). We identified that the pharmacological activity of capsanthin on adipogenesis in 3T3-L1 was mainly due to its adrenoceptor-${\beta}_2$-agonistic activity. In high-fat diet animal model study, capsanthin significantly enhanced spontaneous locomotive activities together with progressive weight-loss. The capsanthin-induced activation of kinetic behavior in mice was associated with the excessive production of ATP initiated by both the enhanced lipolytic activity together with accelerated oxidation of fatty acids due to the adrenoceptor ${\beta}_2$-agonistic activity of capsanthin. Capsanthin also dose-dependently increased adiponectin and p-AMPK activity in high fat diet animals, suggesting that capsanthin has both anti-obesity and insulin sensitizing activities.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.332-335
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• 2011

As our interests in eco-friendly materials have been significantly increased, the utilization of porous zeolite concrete that has structural functionality and permeability has been increased. In this paper, the mixture of porous concrete and zeolite, which can be used as multirole boulders, was investigated for the suitability of an environment-friendly product by evaluating of the water purification ability. The contamination removal rates of BOD, TOC, T-N, and T-P in stagnant water tank were 70.6, 67.0, 57.7, and 50.6%, respectively. Also for the non-point source pollution with the inflow and the outflow, the removal rates of Zn, Pb, BOD, and COD were 99.9, 90.0, 69.2, and 33.5%, respectively. The performance of the heavy metal contamination removal for the porous zeolite showed better than that of stagnant system. Therefore, it is expected that the installation of the porous zeolite concrete can play a role as an eco-friendly products by its high contamination removal.