• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.483-484
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• 2006

$Eu^{3+}$와 $Pr^{3+}$이 첨가된 $SrTiO_3$형광체를 고상반응법으로 제조하였다. $SrTiO_3:Pr$형광체는 $^3P_J(J=0,1,2){\rightarrow}^3H_4$에 의한 490nm 부근의 녹색발광과 $^1D_2{\rightarrow}^3H_4$에 의한 618nm 의 적색발광이 동시에 나타났다. $SrTiO_3:Eu$형광체는 $SrTiO_3:Pr$형광체와 달리 $^5D_0{\rightarrow}^7F_1$에 의한 583nm와 $^5D_0{\rightarrow}^7F_2$에 의한 610nm의 적색발광만 각각 관찰되었다. $SrTiO_3$의 모체에서 $Eu^{3+}$는 inversion sysmmetry를 가짐으로써 610nm의 electric dipole transition 보다는 583nm의 magnetic dipole transition이 강하게 일어났다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.6
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• pp.468-472
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• 2011

Conductive $SrMoO_3$ thin films were fabricated by RF magnetron sputtering with the powder-type sputtering target, and annealed for crystallization. When RTP (rapid thermal processing) in vacuum was applied, the fabricated thin films showed the mixed phases of $SrMoO_3$ and $SrMoO_4$, but $SrMoO_3$ phase could be promoted by the lowering of the working pressure during deposition. In order to eliminate $O_2$ gas during deposition and annealing, further lowering of the working pressure and furnace annealing in hydrogen atmosphere were tried. With the optimization of the deposition and annealing conditions, the thin film with nearly single-phase of $SrMoO_3$ was obtained, and it showed good electrical conduction properties with a low resistivity of $2.5{\times}10^{-3}{\Omega}{\cdot}cm$ at room temperature.

• Childhood Kidney Diseases
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• v.20 no.1
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• pp.18-22
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• 2016

Purpose: The previous reports regarding VUR resolution were not precise due to early frequent surgical intervention. We evaluated the spontaneous resolution (SR) rate and the incidence of new renal scars in primary VUR, focusing on severe reflux. Methods: Medical records of 334 patients with primary VUR who were on medical prophylaxis without surgery for 1 to 9 years, were retrospectively reviewed. Medical prophylaxis was initiated with low-dose antibiotic prophylaxis or probiotics. Radioisotope cystourethrography was performed every 1 to 3 years until SR of reflux. New renal scar was evaluated with follow-up $^{99m}Tc$ DMSA renal scan. Results: The SR rates decreased as VUR grades were getting higher (P=0.00). The overall and annual SR were 58.4% and 14.9%/yr in grade IV reflux and 37.5% and 9.3%/yr in grade V reflux. The median times of SR were 38 months in grade IV reflux and 66 months in grade V reflux. The probable SR rates in grade IV and V reflux were 7.8% and 8.9% in the 1st year, 46.0% and 30.8% in the 3rd year and 74.4% and 64.4% in the 5th year. The incidences of new renal scars between low to moderate reflux and severe reflux showed no significant difference (P=0.32). Conclusion: The SR rates of severe primary VUR were higher than previously reported and most new renal scars were focal and mild.

• Korean Journal of Remote Sensing
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• v.39 no.4
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• pp.395-407
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• 2023

Super-resolution (SR) has great significance in image processing because it enables downstream vision tasks with high spatial resolution. Recently, SR studies have adopted deep learning networks and achieved remarkable SR performance compared to conventional example-based methods. Deep-learning-based SR models generally require low-resolution (LR) images and the corresponding high-resolution (HR) images as training dataset. Due to the difficulties in obtaining real-world LR-HR datasets, most SR models have used only HR images and generated LR images with predefined degradation such as bicubic downsampling. However, SR models trained on simple image degradation do not reflect the properties of the images and often result in deteriorated SR qualities when applied to real-world images. In this study, we propose an image degradation model for HR satellite images based on the modulation transfer function (MTF) of an imaging sensor. Because the proposed method determines the image degradation based on the sensor properties, it is more suitable for training SR models on remote sensing images. Experimental results on HR satellite image datasets demonstrated the effectiveness of applying MTF-based filters to construct a more realistic LR-HR training dataset.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.6
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• pp.225-228
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• 2005

We have grown the long persistent $SrAl_2O_4:Eu^{2+},\;Dy^{3+}$ phosphor single crystal by Verneuil method. The obtained single crystals were long persistent phosphorescence peaking at ${\lambda}=520nm$ with a size of about 5 mm diameter, 55 mm length. The melting temperature of $SrAl_2O_4:Eu^{2+},\;Dy^{3+}$ measured $T_{mp}=1968^{\circ}C$. The optimum composition was $SrCO_3:Al(OH)_3:Eu_2O_3:Dy_2O_3$ = 1 : 2 : 0.015 : 0.02. Flow rate of $H_2:O_2$ is about 4 : 1. Growthing rate is about 5 mm/hr. The spectra of the phosphorescence from the crystals are quite similar to those obtained with sintered powders used for luminous pigments. The crystalline structure of long persistent $SrAl_2O_4:Eu^{2+},\;Dy^{3+}$ phosphor single crystal was determined by X-ray diffraction.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.49-51
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• 1997

New complex perovskite compounds (Na0.5Sr0.5)(Ti0.5Nb0.5)O3, (Na0.5Sr0.5)(Zr0.5Ti0.5)O3 and (Na0.5Sr0.5)(Ti0.5Ta0.5)O3 have been prepared. The crystal structures of these compounds were determined by powder X-ray Rietveld analysis. The crystal structure of (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 and (Na0.5Sr0.5)(Zr0.5Ta0.5)O3 was Pmmn, and that of (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 was I4/mmm. All these compounds showed the superstructure due to the oxygen octahedron distortion. The selected bond distances and bond angles were calculated by the OFFER. The octahedron distortion for each sample, which was measured from the bond distances and bond angles, showed the following order: (Na0.5Sr0.5)(Z0.5Ta0.5)O3> (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 > (Na0.5Sr0.5)(Ti0.5Ta0.5)O3. Dielectric properties were measured for the samples. In this study, the crystal structure and dielectric properties of the new complex perovskite structures and discussed.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.123-128
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• 2009

This study was conducted to evaluate the weight reduction effect of yeast hydrolysate-SR101. Thirty female college students participated in a 6 week weight control program. All subjects were randomly assigned to either the placebo group, YH-SR101 (yeast hydrolysate-SR101) group, or eX diet (product of yeast hydrolysate-SR101) group. The mean energy intake of the placebo group was 1445.2${\pm}$364.0 kcal (carbohydrate: 60.1%, protein: 25.6%, fat: 14.3%), while those of the YH-SR101 and the eX diet group were 1505.6${\pm}$296.2 kcal (carbohydrate: 60.5%, protein: 22.2%, fat: 14.8%) and 1353.8${\pm}$326.3 kcal (carbohydrate: 63.2%, protein: 20.9%, fat: 15.9%), respectively. The placebo group lost 0.19${\pm}$1.14 kg of body weight, while the treatment groups (YH-SR101 and eX diet) lost 1.13${\pm}$0.83 and 1.54${\pm}$0.74 kg of body weight, respectively. There were significant differences in the decrease in body weight between the placebo and the treatment group (p<0.05). There were also significant differences in the decrease in fat mass between the placebo and treatment group (p<0.05). Furthermore, the BMI of the YH-SR101 and the eX diet groups also differed significantly before and after the diet program (p<0.05). Additionally, the BMI and waist size reduction of the treatment groups (YH-SR101 and eX diet group) differed significantly when compared to the placebo (p<0.05). The reduction of the resting metabolic rate (RMR) blood glucose, total-cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride did not differ significantly among groups. Taken together, these findings indicate that consumption of yeast hydrolysate-SR101 and eX Diet may lead to decreased body weight and fat.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.578-584
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• 1995

An aqueous solution of $Ca(OH)_2$ containing a small amount of dissolved $Sr(OH)_2$ was carbonated with $CO_2$ gas, and the effects of the reaction temperature and $Sr(OH)_2$ on the carbonation were investigated. The higher the reaction temperature and the larger the ratio of $Sr(OH)_2(aq)$ to $Ca(OH)_2(aq)$, which amounts to the larger the ratio of $OH^-$ to $CO_2(aq)$, the better pillar aragonite was formed. $Sr(OH)_2$ played an important role in the formation of pillar aragonite, because it is easily formed itself into rhombic $SrCO_3$ during the initial period of carbonation process and acting as a seed for the pillar aragonite of similar morphology. In addition, due to its substantially higher solubility compared with $Ca(OH)_2$, $OH^-$ concentration in the carbonation mixture and subsequently $CO_3^{2-}$ necessary for the crystal growth are increased.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.739-745
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• 1993

The characteristics of mass transfer in an inorganic ion exchange system where Cs and/or Sr are separated by means of zeolites was investigated. Experimental work to separate Cs or Sr was carried out for Cs-AW300 and CS-AW500 systems in case of Cs whereas for Sr-4A and Sr-13X systems in case of Sr. The experimental conditions were chosen as follows in the batch type separation : temperature $25^{\circ}C$, agitation speed 300rpm, amount of zeolite 4g, volume of solution $0.5{\ell}$, and concentrations of solution 1000ppm, 2000ppm, respectively. As a result, it was found that the mass transfer rate is controlled mainly by the liquid film diffusion. The mass transfer coefficients in the film were found to be in the range of $10^{-4}{\sim}10^{-3}cm/sec$, while the apparent diffusivity inside the particles was found to be in the order of $10^{-8}cm^2/sec$.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.189-199
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• 2007

Objective : This study was observed the variation of components from Scutellariae Radix (SR) by processing and storage. Methods : The main component of SR is analysed after various processing and also storage condition by HPLC. Result : 1. In wine-fried SR, the contents of baicalein, wogonin and oroxylin-A was significantly increased. However, the content of baicalin was decreased slightly. In charred SR, the contents of baicalein, wogonin and oroxylin- A was significantly increased. However, the content of baicalin was decreased greatly. 2. The contents variation of SR was not almost changed in room and cold condition. But in accelerated condition, the content of baicalin was slightly decreased, and the contents of baicalein, wogonin and oroxylin-A was significantly increased. 3. The contents variation of wine-fried SR was not almost changed in room and cold condition. But in accelerated condition, the content of baicalin was signifjcantly decreased. 4. The contents variation of charred SR was not almost changed in all conditions. Conclusion : The bioactivity of SR and wine fried SR might be changed by the contents varition during longterm storage. charred SR can be preserved more than two years in room and cold condition.