• 전기화학회지
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• 제15권1호
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• pp.27-34
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• 2012

열처리 온도를 $600^{\circ}C$와 $800^{\circ}C$로 다르게 하여 비정질 및 결정질구조의 탄소를 포함하는 $Li_3V_2(PO_4)_3/C$분말을 각각 합성하였으며, 결정성에 따른 리튬 이차전지용 음극으로의 특성을 비교하였다. 결정질 $Li_3V_2(PO_4)_3/C$은 추가반응에 의하여 리튬이 저장되기 때문에 260 mAh $g^{-1}$의 제한된 용량만을 지니고 있음에 비하여, 비정질 $Li_3V_2(PO_4)_3/C$는 3가의 바나듐이 금속상태에 근접할 정도로 가역적으로 반응되어 460 mAh $g^{-1}$의 큰가역용량을 발현함을 확인하였다. 이는 비정질 구조에서 기인하는 특성으로 유연한 구조로 인한 새로운 리튬의 저장공간이 확보되는 것 때문이라 할 수 있다. 또한, 비정질 $Li_3V_2(PO_4)_3/C$는 비정질 구조에 기인하는 선형적인 충방전 곡선을 지니고 있어 정확한 충전심도의 예측이 용이할 뿐만 아니라, 결함구조에서 유발된 리튬이온의 향상된 확산성으로 인하여 우수한 속도 특성도 나타내고 있다.

• KSBB Journal
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• 제9권4호
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• pp.436-442
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• 1994

Aspergillus terreus NRRL 1960에 의한 이다콘산의 생산에 관해 연구하였다. pH, 접종량, 배지조성 등의 최적조건을 확립하였다. 이타콘산의 최대생산 량은 37°C, pH 2.5의 조건에셔, 5% (w/v) glu­c cose, 0.5 % (w/v) $NH_4Cl$, 0.2 % (w/v) yeast ex­tract, 0.1 % (w/v) $MgSO_4$, 0.2 % (w/v) NaCI을 포함하는 배지에서 7일만에 $19.18g/\ell$를 얻을 수 있었다. 종균배양 배지로서 2 % malt extract가 적합하였다. 교반식 반응기에서 유리균체에 의한 이타콘 산의 회분식 생산은 플라스크 배양에 비해 비효율적 이었다.

• 동의생리병리학회지
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• 제23권4호
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• pp.925-932
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• 2009

The purpose of this study is to evaluate factors that have correlation with improvement of Cerebrovascular accidents(C.V.A) and to decide ranking of influence about improvement of C.V.A. This observation was made on 153 subjects of C.V.A. that were diagnosed through brain MRI or brain CT. They were hospitalized in the Semyung University Oriental Medicine Hospital from the January 1st 2006 to December 31th 2007. The subjects of this study are divided into two groups. The one group has slight motor disturbance, and the other group has severer motor disturbance. Based on medical treatment chart, we analyze differences of many factors like past history, family history, drinking, smoking, several symptoms with C.V.A., etc between two groups. As a result, The past history of cerebrovascular disease and past history of hypertension are the most influencing factors in improvement of C.V.A.

• Journal of the Korean Physical Society
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• 제73권9호
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• pp.1356-1361
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• 2018

Replacing conventional Si diodes with SiC diodes in Si insulated gate bipolar transistor (IGBT) modules is advantageous as it can reduce power losses significantly. Also, the fast switching nature of the SiC diode will allow Si IGBTs to operate at their full high-switching-speed potential, which at present conventional Si diodes cannot do. In this work, the electrical test results for Si-IGBT/4HSiC-Schottky hybrid substrates (hybrid SiC substrates) are presented. These substrates are built for two voltage ratings, 1.7 kV and 3.3 kV. Comparisons of the 1.7 kV and the 3.3 kV Si-IGBT/Si-diode substrates (Si substrates) at room temperature ($20^{\circ}C$, RT) and high temperature ($H125^{\circ}C$, HT) have shown that the switching losses in hybrid SiC substrates are miniscule as compared to those in Si substrates but necessary steps are required to mitigate the ringing observed in the current waveforms. Also, the effect of design variations on the electrical performance of 1.7 kV, 50 A diodes is reported here. These variations are made in the active and termination regions of the device.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.71-74
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• 2000

Pt/Pb$TiO_3$/$SrTiO_3$/p-Si films were prepared by metallo-organic solution deposition(M0SD) method and investigated its structure and ferroelectric properties. Crystallinity of specimen as a funtions of post annealing temperature and the thickness of $SrTiO_3$(STO) buffer layer was studied using XRD and AFM. Based on C-V and P-E curve, $PbTiO_3$(PTO) capacitors showed good ferroelectric hysteresis arising from the polarization switching properties. When the thickness of ST0 buffer layer between PTO and Si substrate was 260 nrn and the post annealing temperature was $650^{\circ}C$, it was showed that production of the pyrochlore phase due to interdiffusion of Si into FTO was prevented. The dielectric constant of FTO thin films calculated from a maximum Cma in the accumulation region was 180 and the dielectric loss was 0.30 at 100 kHz frequency. The memory window in the C-V curve is 1.6V at a gate voltage of 5V.

• 한국군사과학기술학회지
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• 제19권1호
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• pp.84-94
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• 2016

The warfighting experimentation is the most important for the weapon acquisition process because the warfighting experimentation shall support the operation effectiveness as well as acquisition logicality. Therefore, ROK Navy is starting to set up the next generation warfighting experimentation systems. According to literature studies, there have been many studies regarding the interoperability of Simulators(Virtual) and Exercising models(Constructive), but not for studies regarding interoperability between Simulators(Virtual) and Analysis models(Constructive) that is the core component of next generation maritime warfighting experimentation systems. This study is dealing with the V-C(Analysis model) interoperability test and methodology of interoperation analysis. The purpose of the study is to provide the new analysis methodology through V-C(Analysis model) interoperation, which can be applied for the concept of operations(CONOPS) of next generation maritime warfighting experimentation systems. In addition to that, the study validates the suggested analysis methodology by the case study of a naval operation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.192-194
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• 2004

At present, application of PSS/E input data for power flow , stability and fault analysis consist of only 154kV and over data(except 22.9kV data). 22.9kV(5.C) Static Condenser is in operation and installation at 22.9kV Bus of 154kV Substation. however, we assume that 22.9kV 5.C install at 154kV Bus. so, we need to study and search about critical limit for 154kV Bus standard operating Voltage according to 22.9kV 5.C Modeling Site by PSS/E Ver28

• 대한한의학방제학회지
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• 제12권1호
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• pp.209-223
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• 2004

Objective: This study was conducted to investigate the effects of Coptidis Rhizoma on the plasma IL-6 and $TNF-{\alpha}$ level in mice by intracerebroventricular(I.C.V.) injection of Lipopolysaccharide (LPS). Method: 6 mice were assigned to each of the Normal group, the Control group, and the individual Experimental groups. In the Normal group only saline was administered intragastrically, and in the Control group LPS was injected intracerebroventricularly 1 hr after intragastric administration of saline. In the Experimental groups Coptidis Rhizoma(0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS (100ng/mouse) I.C.V. Injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital venous plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of plasma IL-6 and $TNF-{\alpha}$. Result: 1. LPS I.C.V. Injection increased plasma IL-6 level significantly in a dose-dependent manner compared with Normal group. (P<0.01) The plasma IL-6 concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 2. Both the 0.5g/kg(Sample A) and 1.0g/kg(Sample B) groups to which Coptidis Rhizoma was administered intragastrically 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed insignificant lower plama IL-6 level in 1 hr than Control group(P>0.05), and 3.0g/kg group(Sample C) conversely showed higher plama IL-6 level than Control group. 3. LPS I.C.V. Injection increased plasma $TNF-{\alpha}$ level significantly in a dose-dependent manner compared with Normal group.(P<0.05) The plasma $TNF-{\alpha}$ concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 4. All Sample groups(0.5g/kg, 1.0g/kg, and 3.0g/kg) to which Coptidis Rhizoma was administered intragastrically with each constituent-dose 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed significant lower $TNF-{\alpha}$ plama level in 1 hr than Control group.(P<0.001) These data revealed that Coptidis Rhizoma might have anti inflammatory effect by reducing the plasma $TNF-{\alpha}$ level in a dose dependent manner in mice LPS I.C.V. Injection.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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• pp.35-36
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• 2009

In this work, we demonstrate 800V 4H-SiC power DMOSFETs with several structural alterations to obtain a low threshold voltage ($V_{TH}$) and a high figure of merit ($V_B^2/R_{SP,ON}$). To optimize the device performance, we consider four design parameters; (a) the doping concentration ($N_{CSL}$) of current spreading layer (CSL) beneath the p-base region, (b) the thickness of p-base ($t_{BASE}$), (c) the doping concentration ($N_J$) and width ($W_J$) of a JFET region, (d) the doping concentration ($N_{EPI}$) and thickness ($t_{EPI}$) of epi-layer. These parameters are optimized using 2D numerical simulation and the 4H-SiC DMOSFET structure results in a threshold voltage ($V_{TH}$) below ~3.8V, and high figure of merit ($V_B^2/R_{SP,ON}$>${\sim}200MW/cm^2$) for a power MOSFET in $V_B$-800V range.

• Kyungpook Mathematical Journal
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• 제57권4호
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• pp.667-676
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• 2017

We study the positive $C^1$ function z = f(x, y) defined on the plane ${\mathbb{R}}^2$. For a rectangular domain $[a,b]{\times}[c,d]{\subset}{\mathbb{R}}^2$, we consider the volume V and the surface area S of the graph of z = f(x, y) over the domain. We also denote by (${\bar{x}}_V,\;{\bar{y}}_V,\;{\bar{z}}_V$) and (${\bar{x}}_S,\;{\bar{y}}_S,\;{\bar{z}}_S$) the geometric centroid of the volume under the graph of z = f(x, y) and the centroid of the graph itself defined on the rectangular domain, respectively. In this paper, first we show that among nonconstant $C^2$ functions with isolated singularities, S = kV, $k{\in}{\mathbb{R}}$ characterizes the family of catenary rotation surfaces f(x, y) = k cosh(r/k), $r={\mid}(x,y){\mid}$. Next, we show that one of $({\bar{x}}_S,\;{\bar{y}}_S)=({\bar{x}}_V,\;{\bar{y}}_V)$, $({\bar{x}}_S,\;{\bar{z}}_S)=({\bar{x}}_V,\;2{\bar{z}}_V)$ and $({\bar{y}}_S,\;{\bar{z}}_S)=({\bar{y}}_V,\;2{\bar{z}}_V)$ characterizes the family of catenary rotation surfaces among nonconstant $C^2$ functions with isolated singularities.