• 동의생리병리학회지
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• 제21권3호
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• pp.626-633
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• 2007

To access the safety and efficacy of Chungyeoldodam-tang(CDT), a traditional herbal medicine prescription, on hypertension we examined various parameters involved in the pathogenesis of hypertension. CDT seems to be safe because CDT at the concentrations lower that 250 ug/ml showed no toxic effects in cultured human fibroblast and no toxic effects on liver function. The production of reactive oxygen species (ROS) were greatly decreased in CDT treated group compared with control, and angiotensin converting enzyme activities were reduced by CDT in a dose dependent manner. There was no differences in weight of hearts between control and CDT treated group. The blood pressure and pulse rate were significantly decreased. CDT greatly reduced the levels of plasma hormones including aldosterone, dopamine, and norepinephrine, but not epinephrine, and serum electrocytes including Na$^+$ and Cl$^-$, but not K$^+$. were also decreased. The levels of uric acid, BUN and creatinine were significantly decreased compared with control. These results suggested that CDT has suppressive effects on various pathologic factors in hypertension, and CDT has potential as a safe and effective therapeutics for hypertension.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1244-1247
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• 2005

The material removal mechanism of Electrical Discharge Machining (EDM) process has been studied for several decades. However, understanding of the material removal mechanism is still a difficult problem because the mechanism involves complicated physical phenomena including plasma. Especially, for a micro-EDM process, due to the influence of the debris that is generated during the machining process, quantitative modeling of EDM becomes more complex. To understand better the effects of the debris in the micro-EDM process experimentally, a new approach has been introduced in this study. Using a specially designed workpiece holder, the debris generated during the EDM with various process conditions has been collected. Then, using a simulated environment using micro-sized metal powders, the influence of the debris during the single EDM discharge has been observed. The effects of EDM process parameters on the debris size and product quality are discussed.

• 한국진공학회지
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• 제10권4호
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• pp.440-448
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• 2001

논문에서는 원통형 및 평판형 반응기에 20 kV의 사각파형 펄스전원을 인가하여 대기압 절연막 방전 플라즈마 반응기의 동작특성을 관찰하였다. 전류-전압파형과 하전량-전압곡선을 관찰한 결과 반응기의 정전용량 크기에 따라서 최적의 운전효율을 갖는 최적운전주파수 $f_0$가 $f_0\proptoexp(-C)$의 관계를 갖고 있음을 알았다. 이 관계를 이용하여 반응기에서 소실되는 소모전력을 구하였다. 반응기의 소모전력은 반응기의 구조와 전극의 유전물질의 종류 등의 함수인 반응기 정전용량 값에 따라서 변화하였으며 반응기의 특정한 정전용량 값에서 최대값을 가졌다. 이 정전용량 값을 이용하여 최적효율을 갖는 DBD 반응기를 설계할 수 있을 것으로 사료된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.182-185
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• 2003

본 논문은 AC PDP의 구조, 전극 및 가스등을 기존 방식 그대로 사용하면서 고휘도 방전모드를 구현할 수 있는 새로운 파형의 유지펄스에 관한 연구 결과이다. 기존 PDP 구조에서의 Plasma 방전은 음극영역에서 주된 방전이 발생하기 때문에 Xenon gas의 여기율이 낮아지게 됨으로 충분한 휘도를 얻을 수가 없었다. 이러한 PDP가 갖는 휘도 특성의 문제를 개선하기 위한 목적으로 Panel의 셀구조의 변형, 전극 구조의 변화 또는 방전 가스의 혼합비율조정 둥 다양한 노력과 시도를 계속하고 있다. 하지만 PDP의 생산 단가의 상승을 초래할 수 있으며, 전극 간격을 조절하여 휘도를 개선하는 방식은 화질의 저하시킬 뿐만 아니라 방전전압을 증가시키게 됨으로 소비전력을 증가시키게 된다. 본 연구에서 제안하는 새로운 방식의 유지방전 구동파형은 기존의 유지 방전 펄스인 스퀘어 펄스와는 다르게 계단형의 펄스를 사용하는 방식으로 방전이 일어나기 전까지 일정한 전압을 인가하여 유지시킨 뒤 어느 시점에서 방전 되기까지 전압을 올려주는 방법으로 PDP의 협소한 방전 영역을 증가 시킴으로써 고휘도를 얻을 수 있다. 실험 결과 기존의 유지펄스와 비교하여 39.4%의 휘도와 50.0%의 효율 향상을 얻을 수 있었다.

• 대한한방내과학회지
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• 제30권4호
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• pp.657-673
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• 2009

This experiment was performed to determine the antihypertensive effect of Yangganhwadam-tang(YHT) on hypertension in spontaneously hypertensive rat. The results obtained were as follows : 1. YHT showed scavenging activity on DPPH free radical and SOD-like activity. 2. YHT significantly decreased heart weight. 3. YHT significantly decreased blood pressure and pulse. 4. YHT significantly decreased the level of plasma aldosterone. 5. YHT significantly decreased the level of norepinephrine. 6. YHT significantly decreased the levels of potassium and calcium. 7. YHT significantly decreased the level of BUN. 8. YHT decreased eosinophilic changes in the heart cells, and dilated renal arterioles stenosis. These results suggest that YHT might be effective in treatment and prevention of hypertension.

• 한국진공학회지
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• 제7권3호
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• pp.255-260
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• 1998

Ionized magnetron sputtering은 high density plasma를 사용하여 스퍼터된 입자의 이온화율을 기판에서의 플럭스 기준으로 80%이상까지 증대시킬 수 있는 방법으로 반도체 소자의 아주 작은 홀이나 via contact등을 채울 수 있는 아주 유용한 수단이나 가스의 압력 이 30mTorr 이상으로 상당히 높아야만 이온화율이 높게 유지되어 스퍼터 증착 속도가 느려 지고 중성입자의 각도 분포가 넓어지는 단점이 있다. 그 원인이 스퍼터된 입자들에 의한 전 자 온도의 급격한 감소와 타겟 주변에서의 가스 희귀화 현상에 있다고 보고 이를 보완하고 자 스퍼터 전력을 펄스화 하는 방법을 고안하여 실험하였다. 그 결과 펄스의 on/off time이 10ms/10ms, 100ms/100ms에서 가장 높은 이온화율을 가시광 분광 결과에서 보였으며 실제 로 Ag의 XRD결과 (111)에서 (200)으로 우선 방위의 현격한 변화가 관찰되었다. 이를 고전 력 스퍼터링에 의한 중성 가스 가열과 냉각의 측면에서 해석하였다.

• 한국진공학회지
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• 제8권4A호
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• pp.482-489
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• 1999

AC PDP(P1asma Display Pane1)s use the mixture of inert gases to generate a discharge inside the display pixels. Impurities such as CO, $CO_2$ and OH inside discharge region may deteriorate the characteristics of PDP operation during long life time of PDP. Electro-negative gas such as CO can cause the sustain pulse amplitude to rise by attaching electrons which will play an important role in the earlier stage of the discharge. MgO film is used to protect the dielectric layer in AC PDP, and is in contact with the free space of display pixel where it is filled with the inert gas mixture. So, MgO film can be a main source of impurities. In this experiment, we observed the change of impurity generation of various MgO films which were deposited by different methods, by using QMS. (quadropole mass spectrometer) The main impurites were $H_2$, CO and $CO_2$. And with the comparison of the TPD (temperature programmed desorption) result, it can be understood that impurity gases are generated by sputtering of MgO surface not by outgassing. Deposition method had effects on the characteristics of the impurity generation. The MgO film manufactured by e-beam evaporation generated more amount of impurity gases than the MgO films manufactured by sputtering or ion-plating. And also heat treatment of MgO film after deposition decreased the magnitude of impurity gas generation.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.739-742
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• 2003

We have compared 2-D and 3-D fluid simulation results of alternating current plasma display panel (AC-PDP) cell with experimentally measured two kinds of excited Xe species $Xe^{\ast}(^{3}P_{1})$ and $Xe^{\ast}(^{3}P_{2})$ characteristics. Although direct experimental access and diagnostics of the discharge in a PDP cell is problematic due to the small cell size, some of experimental technologies have made it possible to diagnose the behavior of excited Xe species [1, 2]. The simulation shows the similar characteristics to the experimental results in the excited Xe species density distribution and the number of excited Xe atoms in anode and cathode region. In certain cases, we obtained the arch-shaped discharge path between two sustain electrodes due to the additional pulse applied to address electrode analogous to experiment. This long path discharge induced higher luminous and discharge efficiency compared to the standard case.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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• pp.103-107
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• 2000

The relationships between driving voltage and the wall charge distribution in the address period of surface discharge type AC Plasma Display Panel have been investigated. The quantity of wall charge on each electrode are detected simultaneously from the electrode current after applying only one addressing discharge pulse. The wall charge Qy on the scan electrode Y is nearly the sum of Qx on the address electrode X and Qz on the sustain electrode Z. The Qy increased with the driving voltage regardless of the kind of electrode, whereas the address time Td decreased, Qz and Qy are increased considerably with the blocking voltage Vz, whereas Qx is decreased. The increase rate of Qx, Qy and Qz for increase in Vz was $-13{\times}10^{-2}$ (pc/Vz), and $60{\times}10^{-2}$ (pc/Vz) and $70{\times}10^{-2}$(pc/Vz), respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.149-149
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• 2008

Metal-Insulator-Metal(MIM) capacitors have been studied extensively for next generation of high-density dynamic random access memory (DRAM) devices. Of several candidates for metal electrodes, Ru or its conducting oxide $RuO_2$ is the most promising material due to process maturity, feasibility, and reliability. ALD can be used to form the Ru and RuO2 electrode because of its inherent ability to achieve high level of conformality and step coverage. Moreover, it enables precise control of film thickness at atomic dimensions as a result of self-limited surface reactions. Recently, ALD processes for Ru and $RuO_2$, including plasma-enhanced ALD, have been studied for various semiconductor applications, such as gate metal electrodes, Cu interconnections, and capacitor electrodes. We investigated Ru/$RuO_2$ thin films by thermal ALD with various deposition parameters such as deposition temperature, oxygen flow rate, and source pulse time. Ru and $RuO_2$ thin films were grown by ALD(Lucida D150, NCD Co.) using RuDi as precursor and O2 gas as a reactant at $200\sim350^{\circ}C$.