• Journal of the Korean Ceramic Society
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• v.30 no.11
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• pp.925-932
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• 1993

The perovskite phase in PZN-PMN-PT (Pb(Zn, Mg)1/3Nb2/3O3-PbTiO3) pseudoternary ceramics was stabilized by the addition of excess constituent divalent oxides (PbO, MgO and ZnO). The excess addition of 5mol% MgO or 7.5mol% PbO fully stabilized the perovskite phase. The enhanced diffuse phase transition (DPT) and the decrease in the electrical resistivity observed in the presence of excess ZnO or MgO were interpreted in terms of the additional formation of negatively charged, short-range ordered 1:1 domains with a concomitant generation of charge carriers, holes.

• Journal of Power Electronics
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• v.15 no.6
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• pp.1446-1455
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• 2015

This paper illustrates resonant tank design considerations and the implementation of a LLC resonant converter with a wide battery voltage range based on the fundamental harmonic approximation (FHA) analysis. Unlike the conventional design at zero load, the parameter K (the ratio of the transformer magnetizing inductor L_m to the resonant inductor L_r) of the LLC converter in this paper is designed with two charging points, (V_{o_min}, I_{o_max1}) and (V_{o_max}, I_{o_max2}), according to the battery charging strategy. A 2.9kW prototype with an output voltage range of 36V to 72V dc is built to verify the design. It achieves a peak efficiency of 96%.

• Journal of the Korean Magnetics Society
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• v.17 no.1
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• pp.6-9
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• 2007

The generation of entanglement is a very important subject in the quantum computer. Here we suggest the method that generates entanglement between two spin-1/2 particles by using the third moving spin-1/2 particle. We use the $F\"{o}rster$ interaction and the exchange interaction to make the entangled state.

• Current Optics and Photonics
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• v.2 no.6
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• pp.606-611
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• 2018

Measurement of the nonlinear optical coefficients is not an easy task since it requires complicated experimental setup and analysis. We suggest an easy way to estimate the relative nonlinear optical tensor components by direct measurement of the output powers of the second harmonic generation and spontaneous parametric down conversion experiments. The experiments were done in quasi-phase-matched type-0 as well as type-1 interactions at similar pump wavelengths in a 5% MgO-doped periodically poled $LiNbO_3$ crystal to obtain the ratio of the nonlinear optical tensor components $d_{33}/d_{31}$ in each experiment. The obtained ratios were then compared with the previously ascertained values [J. Opt. Soc. Am. B, 14, 2268-2294 (1997)].

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.243-248
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• 1980

Experiments were conducted to study on bionomics and control of cutworms; Agrotis tokionis, A. ipsilon, A. fucosa in Suweon, 1978-1979. A. ipsilon and A. fucosa had two or three generations and A. tokionis had one generation a year. A large number of A. toikonis occured at the end of September, and the major peaks of the first generation of A. tokionis and A. fucosa were in mid-June, the second generation in mid-August, and the third generation was at the end of September. These cutworms laid many eggs on the lower surface of curved downward leaf of Chinese cabbage and the larvae later than 3rd instar began to cut the basal part of stem and then pulled into the soil. A parasite of A. tokionis, a braconid wasp, Meteorus rubens, and two unidentified Ichneumnid wasps were found. Mocap and Volaton gave effective control to the cutworms but Volaton should be applied not to contact with plant.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.83-83
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• 2003

In our previous study, glucose deprivation was reported to induce the potentiated death and ATP loss in immunostimulated astroglia. And this vulnerability to glucose deprivation was due to overproduction of nitric oxide (NO) and hydrogen peroxide (H$_2$O$_2$). In the present study, the role of extracellular signal-regulated kinase 1/2 (ERK1/2) in the glucose deprivation-induced death of immunostimulated astroglia was examined. We showed that immunostimulation with LPS+IFN-ν activated the ERKl/2 signal pathway and produced a large amount of NO and H$_2$O$_2$. Generation of NO and H$_2$O$_2$ in immunostimulated astroglia was mediated via ERK1/2 signal pathways, since addition of the ERK kinase (MEKl) inhibitor PD98059 reduced NO and H$_2$O$_2$production. ERK1/2 activation-mediated NO and H$_2$O$_2$ production is due to an activation of iNOS and NADPH oxidase, respectively. Finally, we found that glucose deprivation caused ATP depletion and the augmented death in immunostimulated astroglia, which was also prevented by PD98059 treatment. These results demonstrate that the ERK1/2 signal pathways play an important role in glucose deprivation induced the death in immunostimulated astroglia by regulating the generation of NO and H$_2$O$_2$.

• Journal of Ceramic Processing Research
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• v.23 no.5
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• pp.566-569
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• 2022

In this paper, we have successfully prepared Al-doped Ni-rich LiNi0.91Co0.06Mn0.03O2 cathodes. The structural properties andelectrochemical performances are studied according to Al cationic doping. It can be confirmed that the crystallinity and cationdisordering of Ni-rich LiNi0.91Co0.06Mn0.03O2 were improved by Al doping. Based on such excellent structural quality, theelectrochemical performance of Al doping LiNi0.91Co0.06Mn0.03O2 was superior to that of pristine LiNi0.91Co0.06Mn0.03O2. The Aldoping Ni-rich NCM has an initial discharge capacity of 209.2 mAh g-1. In addition, it shows superior rate capability byshowing capacity retention of 58.5% under a high rate of 6.0 C. Therefore, it can be judged that Al doping LiNi0.91Co0.06Mn0.03O2can be applied to next-generation cathode for long-distance and fast-charging electric vehicles.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.168-172
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• 2011

Alumina powder was added in a general porcelain (Backja) with clay, feldspar and quartz contents to promote the mullite ($3Al_2O_3{\cdot}2SiO_2$) generation in the porcelain. Low melting materials ($B_2O_3(450^{\circ}C)$, $MnO_3(940^{\circ}C)$, CuO($1080^{\circ}C$)) were doped at ~3 wt% to modify the sinterability of porcelain with a high alumina contents and promote the mullite generation. Green body was made by slip casting method with blended slurry and then, they were fired at $1280^{\circ}C$ for 1hr by a $2^{\circ}C/min$. Densifications of samples with high alumina contents (20~30 wt%) were impeded. As the doping contents of low melting materilas increased, the sinterability of samples was improved. The shrinkage rate and bulk density of samples were improved by doping with low melting materials. Mullite phase increased with increasing the low melting contents in the phase analyses. This means lots of alumina and quartz were transformed into mullite phase by low melting contents doping. In the results, high bending strength of samples with high alumina contents was accomplished by improving the densification and mullite generation in the porcelain.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.464-472
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• 2009

The aim of this study was to investigate the effects of Cheonghyul-san on the generation of peroxynitrite ($ONOO^-$), nitric oxide (NO) and superoxide anion radical ( ${\cdot}\;O_2^-$), and on the expression of NF-${\kappa}$B-dependent proinflammatory proteins in ob/ob mice. Mice were grouped and treated for 5 weeks as follows. Both the normal lean (C57BL/6J black mice) and control obese (ob/ob mice) groups have received the standard chow. The experimental groups were fed with a diet of chow supplemented with 7.5, 15 and 30 mg Cheonghyul-san per 1 kg of body weight for 14 days. For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein-2 (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Western blot was performed using anti-IKK-${\alpha}$, anti-phospho I${\kappa}$B-${\alpha}$, anti-NF-${\kappa}$B (p50, p65), anti-COX-2, anti-iNOS, anti-VCAM-1 antibodies, respectively. Cheonghyul-san prevented $H_2O_2$-induced cell death. Cheonghyul-san inhibited the generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ in the $H_2O_2$-treated LLC-$PK_1$ cells. The generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ were inhibited in the Cheonghyul-san-administered ob/ob mice groups. The GSH/GSSG ratio was decreased in the ob/ob mice, whereas the ratio was improved in the Cheonghyul-san-administered groups. Cheonghyul-san inhibited the protein expression levels of phospho-I${\kappa}$B-${\alpha}$, IKK-${\alpha}$, NF-${\kappa}$B (p50, p65), COX-2, iNOS and VCAM-1 genes. These results suggest that Cheonghyul-san is an effective scavenger of $ONOO^-$, ${\cdot}\;O_2^-$ and NO, and has an inhibitory effect on the expression of NF-${\kappa}$B-dependent inflammatory genes in ob/ob mice. Therefore, Cheonghyul-san might be used as a potential therapeutic drug against the diabetes- and obesity-related proinflammatory diseases.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.250-254
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• 1989

Second-harmonic generation at a silver-electrolyte (0.1 M KCL + H2O) interface was enhanced by surface roughness. The intensity of the second-harmonic radiation was shown to be sensitive enough to detect molecular monolayers adsorbed on a silver surface.