• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.193-203
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• 2018

The operational aerosol retrieval algorithm for the Moderate Resolution Imaging Spectroradiometer (MODIS) measurements was recently updated and named collection 6 (C6). The C6 MODIS aerosol algorithm, a substantially improved version of the collection 5 (C5) algorithm, uses an enhanced aerosol optical thickness(AOT) retrieval process consisting of new surface reflection and aerosol models. This study reports on the estimation and validation of the two latest versions, the C5 and C6 MODIS aerosol products over the East Asian region covering $20^{\circ}N$ to $56^{\circ}N$ and $80^{\circ}E$ to $150^{\circ}E$. This study also presents a comparative validation of the two versions(C5 and C6) of algorithms with different methods(Dark Target(DT) and Deep Blue (DB) retrieval methods) from the Terra and Aqua platforms to make use of the Aerosol Robotic Network (AERONET) sites for the years 2000-2016. Over the study region, the spatially averaged annual mean AOT retrieved from C6 AOT is about 0.035 (5%) less than the C5 counterparts. The linear correlations between MODIS and AERONET AOT are R = 0.89 (slope = 0.86) for C5 and R = 0.95 (slope = 1.00) for C6. Moreover, the magnitude of the mean error in C6 AOT-the difference between MODIS AOT and AERONET AOT-is 40% less than that in C5 AOT.

• Journal of Mechanical Science and Technology
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• v.17 no.9
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• pp.1339-1348
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• 2003

Several factors, including peak dp/dt of the ventricular pressure and maximum closing velocity of leaflet have been studied as indices of the cavitation threshold. In the present study, just before closing velocity of the leaflet has been studied as indices of the cavitation threshold, and cavitation erosion on the surface of a mechanical valve was examined by focusing on squeeze flow and the water hammer phenomenon during the closing period of the valve. A simple solenoid-actuated test device that can directly control the valve closing velocity was developed, and opening-closing tests of 3,000 and 40,000 cycles were performed at various closing velocities. There was a closing velocity threshold to occur erosion pitting of valve surface, and its value was about 0.4 m/s in this study. Cavitation-induced erosion pits were observed only in regions where squeeze flow occurred immediately before valve closure On the other hand, the number of the pits was found to be closely related to an area of water hammer-induced pressure wave below the critical pressure defined by water vapor pressure. Therefore, it was concluded that cavitation is initiated and augmented by the two pressure drops due to squeeze flow and water hammer phenomenon, respectively.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.195-198
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• 1999

A Bi$_4$Ti$_3$O$_{12}$ (BIT) thin film is prepared by sol-gel method using acetate precursors and evaluated whether it could be applied to NVFRAM. The drying and the annealing temperature are 40$0^{\circ}C$ and $650^{\circ}C$, respectively and they are determined from the DT-TG analysis. The BIT thin film deposited on Pt/Ta/SiO$_2$/Si substrate shows orthorhombic perovskite phase. The grain size and the surface roughness are about 100 nm and 70.2$\AA$, respectively. The dielectric constant and the loss tangent at 10 KHz are 176 and 0.038, respectively, and the leakage current density at 100㎸/cm is 4.71$mutextrm{A}$/$\textrm{cm}^2$. In the results of hysteresis loops measured at $\pm$250㎸/cm, the remanent polarization (Pr) and the coercive field (Ec) are 5.92$mutextrm{A}$/$\textrm{cm}^2$ and 86.3㎸/cm, respectively. After applying 10$^{9}$ square pulses of $\pm$5V, the remanent polarization of the BIT thin film decreases as much as about 33% from 5.92 $\mu$C/$\textrm{cm}^2$ of initial state to 3.95 $\mu$C/$\textrm{cm}^2$.

• Journal of Environmental Science International
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• v.14 no.7
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• pp.711-717
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• 2005

A magenta azomethine dye(D) was synthesized from the reaction of 3-methyl-1-phenyl-2-pyrazoline-5-one with N,N-diethyl-1,4-phenylenediamine. The magenta azomethine dye was identified on the basis of elemental analysis, $^{13}C-NMR$, infrared, and GC/MS studies. The magenta azomethine dye was decomposed in a basic solution. Rate constants of the fading reaction of magenta azomethine dye in ethanol-water solvent were measured spectrophoto­metrically at 540 nm. Reaction rate was increased with the increase of $[OH\^{-}]\;and\;[H\_{2}O]$ in the region of $[H_{2}O]=11\~40\;M$. The reaction was governed by the following rate law. -d[D]/dt = $\{k_o\;+\;k_{OH}[OH^-][H_{2O}]\}[D]$ A possible mechanism consistent with the empirical rate law has been proposed.

• East Asian mathematical journal
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• v.40 no.1
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• pp.1-23
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• 2024

Let M be a semi-invariant submanifold of codimension 3 with almost contact metric structure (𝜙, 𝜉, 𝜂, g) in a complex space form M_n+1(c). We denote by A, K and L the second fundamental forms with respect to the unit normal vector C, D and E respectively, where C is the distinguished normal vector, and by R_𝜉 = R(𝜉, ·)𝜉 the structure Jacobi operator. Suppose that the third fundamental form t satisfies dt(X, Y) = 2𝜃g(𝜙X, Y) for a scalar 𝜃(≠ 2c) and any vector fields X and Y , and at the same time R_𝜉K = KR_𝜉 and ∇_{𝜙∇𝜉𝜉}R_𝜉 = 0. In this paper, we prove that if it satisfies ∇_𝜉R_𝜉 = 0 on M, then M is a real hypersurface of type (A) in M_n(c) provided that the scalar curvature $\bar{r}$ of M holds $\bar{r}-2(n-1)c{\leq}0$.

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.410-421
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• 1993

Phase equilibria and reaction paths of the superconducting phases and other compatible phases at $850^{\circ}C$ in the Bi-Sr-Ca-Cu-O system were studied. $Bi_2O_3$ was added to $Sr_2CaCu_2O_x$ by 5% up to 40 mole% Bi in the pseudo-binary $Bi_2O_3-(Sr_2CaCu_2O_x)$ system and the heat treated samples were analysed using XRD. SEM, EDS. and DT A. When Bi contents were greater than 35 mole% Bi, liquid phase was formed which was compatible with $Bi_2Sr_2CaCu_2O_8$ phase. The m.p. of $Bi_2Sr_2CaCu_2O_8$ phase decreased as the content of (Sr+Ca)decreased. $Bi_{2+x}Sr_2CaCu_2O_8$ phase first segregated out of liquid phase around $Bi_2Sr_2CaCu_2O_8$ phase during cooling of liquid phase.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.338-343
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• 2003

Various factors, such as the adsorption pH, adjuvant dose, and adjuvant age, which affect the adsorption degree and immunogenicity of an antigen, were investigated. In addition, the effect of pH, antigen content, and adjuvant content on immunogenicity was also studied through animal experiments. Within the ranges studied, a low pH for adsorption, freshly preformed gel, and low pH formulation for the combined DTwP-HepB vaccine were preferrable for the adsorption of the antigens. In addition, a higher DT content was found to have a positive effect on the HBsAg immunogenicity in the combined vaccine. Accordingly, considering the factors affecting the adsorption rate and immunogenicity of the antigens, a novel DTwP-HepB vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $24\;\mu\textrm{g}$ of HBsAg, $24\;\mu\textrm{g}\;Al/ml\;of \;Al(OH)_3\;gel,\;776\;\mu\textrm{g}\; Al/ml\;of\;AIPO_4\;gel$, and pH 7.1) was developed, whose immunogenicity was comparable to the case of administrating, separately and simultaneously, a combined DTwP vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $300\;\mu\textrm{g}\;Al/ml\;of\; AIPO_4\;gel$, and pH 7.1) and mono HepB vaccine [$Hepavax^{\circledR},\;24\;\mu\textrm{g}/ml$ of HBsAg and $500\;\mu\textrm{g}\;Al/ml\;of\;Al(OH)_3\;gel$], which satisfies the potency criteria of the K-FDA for a combined DTwP vaccine and mono HepB vaccine.

• Journal of Pharmacopuncture
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• v.21 no.3
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• pp.159-167
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• 2018

Objectives: Myocardial reperfusion is the only logical cure for ischemic heart disease. However, ischemic-reperfusion (I/R) injury is one of the underlying factors facilitating and accelerating the apoptosis in the myocardium. This study set to investigate the impact of Teucrium polium (TP) hydro-alcoholic extract on I/R induced apoptosis in the isolated rat heart. Methods: Isolated rat hearts were classified into six groups. The control samples were subjected to 80 min of perfusion with Krebs-Henseleit bicarbonate (KHB) buffer; in control-ischemia group, after primary perfusion (20 min) the hearts were exposed to global ischemia (20 min) and reperfusion (40 min). Pretreated groups were perfused with $500{\mu}M$ of vitamin C and various TP concentrations (0.5, 1, 2 mg/ml) for 20 min, and then the hearts were exposed to ischemia and reperfusion for 20 min and 40 min, respectively. Cardiodynamic parameters including rate pressure product (RPP), heart rate (HR), the maximum up/down rate of left ventricular pressure (${\pm}dp/dt$), left ventricular developed pressure (LVDP), and coronary artery flow (CF) were achieved from Lab Chart software data. The Bax and BCl-2 gene expressions were measured in heart samples. Results: Hearts treated with TP extract and vit C represented a meaningful improvement in cardiac contractile function and CF. The overexpression of Bcl-2, downregulation of Bax, and improvement of apoptotic index (Bax/Bcl-2) were observed in pretreated TP extract and vit C hearts. Conclusion: The TP extract was found to ameliorate the cardiac function in the reperfused myocardium. Also, it can hinder apoptotic pathways causing cardioprotection.

• Journal of Technologic Dentistry
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• v.8 no.1
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• pp.91-99
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• 1986

In order to evaluate the community dental health level the actual health capacity of the lower-first permanent molar is suitable as a indicator for assessment. So we had surveyed decayed, missed and filled lower permanent first molar of 460 persons who were in the age from 20 to 29 in Iri City. The obtained results were as follows: 1. The DMFT indices of the lower first permancent molars showed in 1.40 in the age group of from 20 to 24 and 1.44 from 25 to 29. 2. The actual dental health capscities of the lower first permanent molars showed in 84.86% in the age group of from 20 to 24 and 81.03% from 25 to 29. 3. The DMF indices of the lower first permanent molars showed 15.15% in the age group of from 20 to 24 and 18.98% of from 25 to 29. 4. The DMF rates of the lower first permanent molars showed 85.66% in the age group of from 20 to 24 and 88.70% of from 25 to 29. 5. The DMF rates of the lower first permanent molars showed 70.00% in the age group of from 20 to 24 and 71.96% of from 25 to 29. 6. The DT rates of the lower first permanent molars showed 48.84% in the age group of from 20 to 24 and 39.55% of from 25 to 29. 7. The FT rates the lower first permanent molars showed 40.22% in the age group of from 20 to 24 and 43.98% of from 25 to 29. 8. The MT rates of the lower first permanent molars showed 10.94% in the age group of from 20 to 24 and 16.17% of from 25 to 29.

• Journal of the Korean Society of Food Science and Nutrition
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• v.10 no.1
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• pp.53-60
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• 1981

Dehydration phenomena has been studied for the shiitake mushroom Lentinus edodes sanryun No.1, through which examine the effect of temperature and air velocity and derivation of its kinetics. Temperature effect for the dehydration rate constant were examined under the constant air velocity (1.5m/sec) with the variation of temperature from $40^{\circ}C$ to $55^{\circ}C$. Water content were reduced exponentially with the course of time and calculated dehydration rate constant values varies with temperature with an Arrhenius-type relationship, which had been expected in the chemical reaction kinetics. Influence of air velocity for the dehydration rate constant under the constant temperature $(45^{\circ}C)$ showed interesting results. For the range 1.0m/sec to 2.0m/sec, dehydration rate constant values are increased with the air velocity, but for the 2.0 to 3.1m/sec, dehydration rate constant values are decreased which were caused by case hardening. One of the selected conditions in the optimal dehydration range, temperature $50^{\circ}C$, air velocity 2m/see, and its measured humidity 38-41%, mathematical model of dehydration curve and dehydration rate equations were developed and the resulting kinetic models were X=6.94 $e^{-0.345t}$ and dx/dt = -2.39 $e^{-0.345t}$