• Journal of the Korean Vacuum Society
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• v.19 no.3
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• pp.184-189
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• 2010

Organic light-emitting diodes (OLEDs) with single emissive layer structures using two fluorescent dopants were fabricated and the device was composed of ITO / NPB ($700{\AA}$) / MADN : C545T - 1.0% : DCJTB - 0.3% ($300{\AA}$) / Bphen ($300{\AA}$) / LiF ($10{\AA}$) /Al ($1,000{\AA}$). C545T and DCJTB were functioned as green fluorescent dye and red fluorescent dye under MADN as host material. Concentrations of C545T and DCJTB was changed in emissive layer of MADN. Optimized OLED device using two fluorescence dopants shows emission efficiency of 8.42 cd/A and luminescence of 3169 cd/$m^2$at 6 V with CIE color coordinate, (0.43, 0.50). Electroluminescence of optimized OLED showed two peak at 500 and 564 nm according to C545T and DCJTB. These results indicate that F$\ddot{o}$ster energy transfer energy transfer was from MADN to C545T and rather than to DCJTB continuously.

• Journal of Pharmaceutical Investigation
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• v.21 no.4
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• pp.247-251
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• 1991

Effects of aluminum magnesium hydroxide (A) and cimetidine (C) on the pharmacokinetics of minocycline (M) were investigated in female rats. Blood samples were collected at various time intervals until 36 hrs following oral dosing of drugs. Plasma minocycline concentrations were determined by HPLC. Control group (M), $T_1$ group (M+A), $T_2$ group (A+M after 2 hrs), $T_3$ group (M+A after 2 hrs), $T_4$ group (M+C) and $T_5$ group (C+M after 2 hrs) were divided to examine interaction of the drugs with minocycline. Plasma minocyline level-time curves were well described by two-compartment open model with first-order absorption in rats. Antacid treatment was associated with reduced of 71.0, 45.9, 35.7% in minocycline absorption rate $constant(K_{\alpha})$, maximum plasma $concentration(C_{max})$, and relative $bioavailability(F_{rel})$, respectively. Cimetidine treatment group exhibited no significant changes in plasma level-time curve when compared with control group and did not affect minocycline absorption as by any of these three parameters.

• International Journal of Reliability and Applications
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• v.12 no.1
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• pp.15-39
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• 2011

This paper deals with the reliability analysis of a complex system with three possibilities at the time of repair. The considered system consists of two subsystems A and Bin series configuration (1-out-of-2: F). Subsystem A has n units which are connected in series whereas subsystem B consists of n units in parallel configuration. The configuration of subsystem A is of 1-out-of-n: F whereas subsystem B is of k-out-of-n: D and k+1-out-of-n: F nature. System has three states: Good, degraded and failed. Supplementary variable technique has been used for mathematical formulation of the model. Laplace transform is being utilized to solve the mathematical equation. Reliability, Availability, M.T.T.F., Busy Period and Cost effectiveness of the system have been computed. The repairs from state $S_7$ to $S_0$, $S_8$ to $S_0$, $S_9$ to $S_0$ and $S_{11}$ to $S_0$ have two types namely exponential and general. Joint probability distribution of repair rate from $S_7$ to $S_0$, $S_8$ to $S_0$, $S_9$ to $S_0$ and $S_{11}$ to $S_0$ is computed by Gumbel-Hougaard family of copula. Some particular cases of the system have also been derived to see the practical importance of the model.

• Bulletin of the Korean Mathematical Society
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• v.47 no.5
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• pp.987-996
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• 2010

In this paper, we investigate the Cauchy-Rassias stability in Banach spaces and also the Cauchy-Rassias stability using the alternative fixed point for the functional equation: $$f(\frac{sx+ty}{2}+rz)+f(\frac{sx+ty}{2}-rz)+f(\frac{sx-ty}{2}+rz)+f(\frac{sx-ty}{2}-rz)=s^2f(x)+t^2f(y)+4r^2f(z)$$ for any fixed nonzero integers s, t, r with $r\;{\neq}\;{\pm}1$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.550-553
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• 2001

In this study, unity current gain frequency f$\_$T/ of GaAs MESFET is predicted with different temperatures up to 400 $^{\circ}C$. Temperature dependence parameters of the device including intrinsic carrier concentration n$\_$i/ effective mass, depletion width are considered to be temperature dependent. Small signal parameters such as gate-source, gate dran capacitances C$\_$gs/ C$\_$gd/ are correlated with transconductance g$\_$m/ to predict the unity current gain frequency. The extrinsic capacitance which plays an important roles in high frequency region has been taken into consideration in evaluating total capacitance by using elliptic integral through the substrate. From the results, f$\_$T/ decreases as the temperature increases due to the increase of small signal capacitances and the mobility degradation. Finally the extrinsic elements of capacitances have been proved to be critical in deciding f$\_$T/ which are originated from the design rule of the device.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.5
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• pp.1304-1308
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• 2008

This study was performed to evaluate the effect of persimmon leaves extract on the reactive oxygen species (ROS) in cultured melanoma cells. The B16/F10 melanoma cells were treated with various concentrations of t-butyl hydroperoxide (t-BHP). And also, the effect of persimmon leaves (PL) extract on the cytotoxicity mediated by t-BHP was done on the cell viability, tyrosinase activity and melanogenesis by colorimetric assays. In this study, t-BHP decreased cell viability in dose-dependent manner and XTT90 and XTT50 values were measured at 10 and 35 uM of PL, respectively in these culture. And also, XTT50 value was assessed as a highly toxic effect on cultured melanoma cells by the toxic criteria. In the effect of PL extract on the t-BHP-mediated cytotoxicity, PL extract significantly increased the cell viability injured by t-BHP in cultured B16/F10 melanoma cells. PL also showed the decreased tyrosinase activity and melanogenesis. From these results, it is suggested that ROS such as t-BHP showed highly toxic effect on cultured melanoma cells, and also, PL extract inhibited the tyrosinase activity and melanogenesis in cultured melanoma cells injured by ROS.

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.53-53
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• 2002

• Bulletin of the Korean Mathematical Society
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• v.36 no.4
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• pp.671-682
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• 1999

Using a base-point free version of the infinite symmetric product we define a fibrewise infinite symmetric product for any fibration $E\;\longrightarrow\;B$. The construction works for any commutative ring R with unit and is denoted by $R_f(E)\;l\ongrightarrow\;B$. For any pointed space B let $G_I(B)\;\longrightarrow\;B$ be the i-th Ganea fibration. Defining $M_R-cat(B):= inf{i\midR_f(G_i(B))\longrihghtarrow\;B$ admits a section} we obtain an approximation to the Lusternik-Schnirelmann category of B which satisfies .g.a product formula. In particular, if B is a 1-connected rational space of finite rational type, then $M_Q$-cat(B) coincides with the well-known (purely algebraically defined) M-category of B which in fact is equal to cat (B) by a result of K.Hess. All the constructions more generally apply to the Ganea category of maps.

• Bulletin of the Korean Mathematical Society
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• v.50 no.2
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• pp.399-405
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• 2013

We explicitly construct a thin basis for the set $\mathbf{M}$ of monic polynomials in one variable $t$ over a finite field ${\mathbb{F}}_q$.

• Journal of Korean Academy of Nursing
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• v.30 no.2
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• pp.413-424
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• 2000

The purpose of this study was to analyze the effect of anticipated variables on hemodialysis that was impact patients' quality of life. The subjects of the study were 104 patients who were over 18 years old. They were enrolled at Kidney dialysis unit in General Hospital located in T and M city, Republic Korea. And the duration of treatment was more than 6 months. They all met the research criteria and agreed to participate in the research. The research instrument have 25 questionnaire which were originally Ferrans' (1985) instrument to measure the quality of life for hemodialysis patients and later changed by Lee, Suk-Ja into the 35 items after eliminating repeated contents, the Cronbach's $\alpha$in this study was .87. The stress instrument was measured by 36 items which were modified and supplemented the instrument developed by Kim, Yong-Kyong(15) for hemodialysis patients, and the Cronbach's $\alpha$was .9333. Depression instrument was 20 questions modified BDI(Beck Depression Inventory) to meet hemodialysis patients' conditions, and Cronbach's $\alpha$ was .92. June 25, 1999 and the data was analyzed by SPSS/PC, and the statistical techniques were ANOVA(variables analysis), Scheffe test, Multiple Regression. The findings of this study were as follows: 1. The effect of general characteristics on hemodialysis patients' quality of life, the characteristics showing a statistically, significant difference were the existence of an occupation(t=6.7353, P= .0109), marital status (F=4.3550, P= .0290), economic status (F=4.6475, P= .0118) and presence of care support (F=2..4738, P= .0494). 2. The effect of general characteristics on the patient's stress, the characteristics showing a significant difference were gender (t= 4.1143, p= .0451), education level (F= 4.3550, p= .008), the existence of an occupation (t=8.7498, p= .0038), and presence of care support(F=3.1715, p= .0169). 3. The effects of general characteristics on depression, the characteristics were education level (F=3.7517, P= .0069), the existence of religion(t=9.4843, p= .0027), an occupation (t=15.3745, p= .0002), marital status (F=3.3400, P= .0223) and presence of care support (F=3.7605, p= .0069). 4. The Multiple Regression is used to identify the effect of anticipated variables on the patient's quality of life. The variables were depression (T=-9.656, P=.000), marital status (T=-2.287, P=.0243) and the regression expression was Y=117.62053 - 1.13618Χ$_1$ + 2.66213Χ$_2$(Χ$_1$: Depression, Χ$_2$ : Marriage), The explanation of the total regression expression appeared to be 52.578%.