• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.835-842
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• 2004

In this paper, we have analyzed the MC-DS/CDMA system with input signal synchronized completely through adjustment of the gain in the PLL loop, by using the hybrid SC/MRC-(2/3) technique, which is said to one of the optimal diversity techniques under the multi-path fading environment, assuming that phase error is defined to the phase difference between the received signal from the multi-path and the reference signal in the PLL of the receiver. Also, assuming that the regarded radio channel model for the mobile communication is subject to the Nakagami-m fading channel, we have developed the expressions and performed the simulation under the consideration of various factor, in the MC/DS-CDMA system with the hybrid SC.MRC-(2/3) diversity method, such as the Nakagami fading index(m), $the\;number\;of\;paths\;(L_p),$ the number of hybrid SC.MRC-(2/3) $diversity\;branches\;(L,\;L_c),$ the number of users (K), the number of subcarriers (U), and the gain in the PLL loop. As a result of the simulation, it has been confirmed that the performance improvement of the system can be achieved by adjusting properly the PLL loop in order for the MC/DS-CDMA system with the hybrid SC/MRC-(2/3) diversity method to receive a fully synchronized signal. And the value of the gain in the PLL loop should exceed 7dB in order for the system to receive the signal with prefect synchronization, even though there might be a slight difference according to the values of the fading index and the spread processing gain of the subcarrier.

• Journal of Korea Water Resources Association
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• v.36 no.3 s.134
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• pp.365-374
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• 2003

This is a study on application of a TVD-Mccormack scheme for the computation of one-dimensional dam-break flows. The TVD scheme not only has the ability to damp out oscillations, but also does not contain terms with adjustable parameters. Moreover, the TVD-McCormack scheme does not cause any additional difficulty when dealing with the source term of the equation and retains second-order accuracy in both space and time. In this study, by appropriately designing the limiter functions, the TVD property can be achieved, and numerical oscillations near a jump discontinuities can be eliminated or reduced. Also, this numerical scheme has less computational errors when the direction of the predictor-corrector step is in the same direction as the shock wane propagation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.643-647
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• 2003

The Methylene Chloride(MC) fraction of Trichosanthis kirilowii Maxim has been investigated anti-tumor activities in vitro. The MC fraction of Trichosanthis kirilowii Maxim significantly inhibited the proliferation of human leukemic U937 cell with an IC50 of approximately 10μg/ml in a dose-dependent manner. We found that the MC fraction upregulated of caspase9 and caspase-3 activity and cleaved PARP expression but it didn't affect bax and bcl-2. which were demonstrated by western blot analysis. Taken together, these results exerted that the MC fraction suppessed human leukemic U937 cell proliferation by inducing apoptosis, suggesting the MC fraction of Trichosanthis kirilowii Maxim is possible to show anti-cancer activity in vivo.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3388-3400
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• 2023

Detailed analysis of the neutron pathway through matter inside the nuclear reactor core is exceedingly needed for safety and economic considerations. Due to the constant development of high-performance computing technologies, neutronics analysis using computer codes became more effective and efficient to perform sophisticated neutronics calculations. In this work, a commercial pressurized water reactor (PWR) presented by Virtual Environment for Reactor Applications (VERA) Core Physics Benchmark are modeled and simulated using a high-fidelity simulation of OpenMC code in terms of criticality and fuel pin power distribution. Various problems have been selected from VERA benchmark ranging from a simple two-dimension (2D) pin cell problem to a complex three dimension (3D) full core problem. The development of the code capabilities for reactor physics methods has been implemented to investigate the accuracy and performance of the OpenMC code against VERA SCALE codes. The results of OpenMC code exhibit excellent agreement with VERA results with maximum Root Mean Square Error (RMSE) values of less than 0.04% and 1.3% for the criticality eigenvalues and pin power distributions, respectively. This demonstrates the successful utilization of the OpenMC code as a simulation tool for a whole core analysis. Further works are undergoing on the accuracy of OpenMC simulations for the impact of different fuel types and burnup levels and the analysis of the transient behavior and coupled thermal hydraulic feedback.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1146-1152
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• 2005

Graft copolymers were synthesized from methylcellulose(MC) and acrylic acid(AA) with active carboxyl groups in the presence of potassium persulfate($K_2S_2O_8$) initiator to enhance adsorption capacity of toxic heavy metal such as $Pb^{2+}$ and $Cu^{2+}$ from wastewater. The resulting grafted copolymers(MC-g-AA/PAA) were mixture of the graft copolymers from MC and AA(MC-g-AA) and polyacrylic acid homopolymers(PAA). The degree of palling was increased with rising concentration of monomer and initiator under the reaction conditions at $60^{\circ}C$, 3 hrs. The water insoluble property of MC-g-AA showed more than 19.7% degree of grafting. So that it could be an adsorbent of heavy metals. Adsorption characteristics of the MC-g-AA were evaluated depending on the degree of grading, pH of wastewater, adsorption time, dosage of MC-g-AA and concentration of heavy metals in the different conditions. Degree of grafting, and initial concentration of heavy metal ions increased, the adsorption amount of $Pb^{2+}$ and $Cu^{2+}$ increased, but added MC-g-AA increased, the adsorption amount per unit weight of $Pb^{2+}$ and $Cu^{2+}$ decreased. The MC-g-AA showed the high $Pb^{2+}$ and $Cu^{2+}$ adsorption amount in the range pH $4{\sim}6$. Also all of $Pb^{2+}$ and $Cu^{2+}$ ions reached in adsorption equilibrium in neighborhood 4 hours. The adsorption of heavy metals described by Freundlich isotherm, it was determined the value of l/n of $Pb^{2+}$ and $Cu^{2+}$ that 0.4294 and 0.3453, respectively.

• The korean journal of orthodontics
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• v.23 no.3 s.42
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• pp.415-425
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• 1993

Fluoride is one of the most potent stimulators of bone formation in vivo. But its direct effects on osteoblast is not yet clear This study was to investigate the effects of Sodium fluoride on alkaline phosphatase(ALP) activity, cAMP formation responsive to parathormone(PTH) and type I $\alpha$ 2 collagen ribonucleic acid (mRNA) level in Murin osteoblast-like (MC3T3-E1) cells. The cells were cultured in $\alpha-Minimal$ essential medium $(\alpha-MEM)$ supplemente with $10\%$ fetal bovine serum (FBS) and then changed to $0.1\%$ FBS with various concentration of Sodium fluoride. The ALP activity was assayed by the method of Lowry with disodium phenyl phosphated as substrate. cAMP formation was measured by Radioimmuno Assay(RIA). Type I $\alpha$ 2 collagen ribonucleic acid(mRNA) expression was studied by Nothern blot analysis. The results were as follows: 1. cAMP level was increased by PTH in MC3T3-E1 cells. 2. Sodium fluoride showed the tendency of inhibitory effects on cAMP responsiveness to PTH in MC3T3-E1 cells. 3. Sodium fluoride increased ALP activity at cocentration of $2{\mu}M,\;4{\mu}M,\;and\;10{\mu}M$ significantly different from control at the 0.001 level. ALP activity revealed maximum value at $10{\mu}M$ in this study. 4. Nothern blot analysis of Sodium fluoride treated cells, using Type I $\alpha$ 2 collagen prove, revealed significant increase at $10{\mu}M$ in MC3T3-E1 cells.

• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.419-424
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• 2016

$H_5PMo_{10}V_2O_{40}$ ($PMo_{10}V_2$) catalyst chemically immobilized on sulfur-containing mesoporous carbon (S-MC) was prepared, and it was applied to the benzyl alcohol oxidation reaction. S-MC was synthesized by a templating method using SBA-15 and p-toluenesulfonic acid as a templating agent and a carbon precursor, respectively. S-MC was then modified to have a positive charge, and thus, to provide sites for the immobilization of $PMo_{10}V_2$. By taking advantage of the overall negative charge of $[PMo_{10}V_2O4_{40}]^{5-}$, $PMo_{10}V_2$ catalyst was immobilized on the S-MC support as a charge matching component. It was revealed that $PMo_{10}V_2$ species were finely and molecularly dispersed on the S-MC via chemical immobilization. In the vapor-phase oxidation of benzyl alcohol, $PMo_{10}V_2$/S-MC catalyst showed higher conversion of benzyl alcohol and higher yield for benzaldehyde and benzoic acid than unsupported $PMo_{10}V_2$ catalyst. The enhanced catalytic performance of $PMo_{10}V_2$/S-MC was due to fine dispersion of $PMo_{10}V_2$ species on the S-MC via chemical immobilization.

• Journal of East-West Nursing Research
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• v.3 no.1
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• pp.96-103
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• 1998

This study was conducted to identify the adaptation process of the families with chronically ill patients. A descriptive comparative research design was used to the subjects of forty families that have stroke patients at an oriental medical hospital. Research tools were Demands of Illness Inventory(Woods, Haberman & Packard, 1987), Relative and Friend Support Index(McCubbin, Patterson & Glynn, 1982), Family Coping-Coherence Index (McCubbin, Larsen & Olson, 1982), Family Hardiness Index(McCubbin, McCubbin & Thompson, 1986), and Family Member Wellbeing Scale(McCubbin, McCubbin & Thompson, 1986). Data were collected from October 7, 1998 to November 7, 1998 at an oriental medical hospital located in IkSan city. The number of cases was forty and the data were analyzed by SPSS $PC^+$. Descriptive statistics of frequency, number, mean and standard deviation were used to report the results. The results were as follows ; 1. There was no significant differences between the two groups on the family stress. 2. There was significant differences between the two groups on the family strength (t value = - 3.09, p value=$.004^{**}$). 3. There was significant differences between the two groups on the family adaptation(t value= -2.08, pvalue=$.05^*$).

• Journal of Nutrition and Health
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• v.51 no.4
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• pp.316-322
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• 2018

Purpose: The Glycyrrhiza uralensis species (Leguminosae) as a medicinal biocompound, and one of its root components, isoliquritigenin (ISL), which is a flavonoid, has been reported to have anti-tumor activity in vitro and in vivo. However, its function in bone formation has not been studied yet. In this study, we tested the effect of Glycyrrhiza uralensis (ErLR) and baked Glycyrrhiza uralensis (EdLR) extracts on osteoblast proliferation, alkaline phosphatase (ALP) activity, and bone-related gene expression in osteoblastic MC3T3-E1 cells. Methods: MC3T3-E1 cells were cultured in various levels of ErLR (0, 5, 10, 15, $20{\mu}g/mL$), EdLR (0, 5, 10, 15, $20{\mu}g/mL$), or ISL (0, 5, 10, 15, $20{\mu}M$) in time sequences (1, 5, and 20 days). Also, isoliquritigenin (ISL) was tested for comparison to those two biocompound extracts. Results: MTT assay results showed that all three compounds (ErLR, EdLR, and ISL) increased osteoblastic-cell proliferation in a concentration-dependent manner for one day. In addition, both ErLR and EdLR compounds elevated the osteoblast proliferation for 5 or 20 days. Extracellular ALP activity was also increased as ErLR, EdLR, and ISL concentration increased at 20 days, which implies the positive effect of Glycyrrhiza species on osteoblast mineralization. The bone-related marker mRNAs were upregulated in the ErLR-treated osteoblastic MC3T3-E1 cells for 20 days. Bone-specific transcription factor Runx2 gene expression was also elevated in the ErLR- and EdLR-treated osteoblastic MC3T3-E1 cells for 20 days. Conclusion: These results demonstrated that Glycyrrhiza uralensis extracts may be useful for preventing osteoporosis by increasing cell proliferation, ALP activity, and bone-marker gene expression in osteoblastic cells.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.514-519
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• 1996

In order to understand the mechanism of action of flavonoids on the drug metabolizing enzyme, cytochrome P450IA1, this study was undertaken to examine the effect of chrysin, morin, myricetin and aminopyrine on the activities of ethoxyresorufin O-deethylase and benzo(.alpha.) pyrene hydroxylase in the liver. In the isolated perfused rat liver that was pretreated with 3-methylcholanthrene (3MC), chrysin, morin, myricetin and aminopyrine inhibited the activity of ethoxyresorufin O-deethylase with concentration dependent manner. The isolated liver perfusion with chrysin, morin, myricetin and aminopyrine showed inhibition on the induction of ethoxyresorufin O- deethylase by 3MC. And also, in mouse liver hepa I cells, 3MC-stimulated the benzo(.alpha.)pyrene hydroxylase activity which was inhibited by chrysin, morin, myricetin and aminopyrine. These results strongly suggested that hydoxylated flavonoids interfered not only the induction of cytochrome P45OIA1 enzymes by 3MC but also the interaction of substrates and enzyme.