• 마이크로전자및패키징학회지
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• 제14권4호
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• pp.1-7
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• 2007

최근 나노임프린트 리소그래피 공정이 마이크로/나노스케일의 소자 개발에 있어서 경제적으로 대량 생산할 수 있는 기술로 주목 받고 있다. 나노 스케일의 패턴을 성공적으로 전사하기 위해서는 폴리머의 기계적 거동에 대한 이해를 바탕으로, 적절한 공정 조건 즉, 압력, 온도, 시간 등의 선택이 필요하다. 본 연구에서는 열-나노임프린트 공정에서의 충전과정을 해석하기 위하여 비선형 유한요소법을 이용하였으며, 폴리머의 거동을 점탄성으로 가정하여 재료의 응력완화 효과를 고려하였다. 해석을 통하여 온도 및 몰드의 패턴형상이 열-나노임프린트 공정에 미치는 영향을 살펴보았다.

• 생약학회지
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• 제17권1호
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• pp.12-18
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• 1986

In order to investigate experimentally the clinical effects of Choweesungchung-Tang that has been widely used in the cardiovascular and neuropsychogenic disease, experimental studies with experimental animals were carried out. The results of these studies were summarized as follows; Suppressive action was not shown on the convulsion induced by strychnine, but significant effect was noted on the convulsion induced by picrotoxin and caffeine. In acetic acid method, analgesic effect was noted. By the rotor rod and wheel cage method, sedative action was noted. A prolongation of hypnotic time induced by pentobarbital-Na was obtained. Relaxing action was noted remarkably on the ileum of mice, also about mice and guinea-pigs, the same effect was recognized on the smooth muscle of the ileum. The expansion of blood vessels by relaxation of smooth muscle and hypotensive action were noted.

• 대한전자공학회논문지TE
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• 제37권2호
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• pp.1-5
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• 2000

금속이온 농도를 변화시켰을때의 IMI-O 고분자 LB막에 대한 단분자막의 거동과 MIM구조의 LB막 소자에 대한 전기 특성 및 유전 특성을 조사하였다. π-A 등온선의 측정에서 금속 이온 농도가 증가함에 따라 단분자가 차지하는 극한 단면적이 증가하였다. 이러한 변화는 금속이온 농도 변화에 따른 금속이온의 강도 증가에 의한 단분자막의 거동의 차이에 의한 것으로 생각된다. 전압-전류 특성에서 ohmic 영역의 기울기로부터 구한 전기전도도는 금속 이온의 농도가 증가할 수록 증가하였다. 이것은 전개분자와 금속이온간의 결합에 의한 극한 단면적의 변화가 전기전도도에 직접적인 관계가 있기 때문으로 생각된다. 한편, 유전 특성에서 금속이온의 농도가 증가할 수록 허수부 유전율이 최대가 되는 주파수 역시 증가하였다. 따라서 금속이온의 증가에 의해 완화시간 γ가 감소되는 것을 알 수 있었다.

• 한국수소및신에너지학회논문집
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• 제30권6호
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• pp.585-592
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• 2019

In this study, a flashing boiling phenomenon of pressurized water jet was numerically studied and validated against an experimental data in the literatures. The volume of fluid (VOF) technique was used to consider two-phase behavior of water, while the homogeneous relaxation model (HRM) model was used to provide the velocity of phase change. During the flashing boiling through a nozzle, a mach disk was observed near nozzle exit because of pressure drop resulting from two-phase under-expansion. The flashing jet structure, local distributions of temperature/vapor volume fraction/velocity, and position of the mach disk were examined as nozzle inlet temperature changed.

• 대한한방내과학회지
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• 제24권2호
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• pp.260-268
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• 2003

Object : This study was undertaken to define the mechanism of GwakHyangJungGiSan-induced relaxation in rabbit common carotid artery contracted by agonists. Method : In order to investigate the effect of GwakHyangJungGiSan on rabbit's contracted vascular ring detached from common carotid artery, vascular ring intact or damaged endothelium was used for the experiment using organ bath. To analyze the mechanism of GwakHyangJungGiSan-induced relaxation, GwakHyangJungGiSan extract was infused into contracted vascular ring which had been pretreated by pretreatment of indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}-nitro-L-arginine(L-NNA)$. Result : GwakHyangJungGiSan blocks an inflow of $Ca^{2+}$ and relaxes vascular ring by the action of Nitric oxide from endothelium. Consequently when GwakHyangJungGiSan is prescribed, a rise in blood pressure by the resistance of peripheral vessel may be controlled to some extent and so it is anticipated that hypertension, a disorder of blood flow from the vascular contraction and vascular disease will be treated well.

• Biomolecules & Therapeutics
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• 제7권1호
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• pp.66-78
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• 1999

In order to investigate the pharmacological properties of New Wonbang Woohwangchungsimwon Liquid (NSCL), effects of Wonbang Woohwangchungsimwon Liquid (SCL) and NSCL were compared. In isolated rat aorta, NSCL and SCL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) regardless to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxing effect of NSCL and SCL. NSCL and SCL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NSCL and SCL significantly decreased heart rate. NSCL and SCL, at high doses, had a negative inotropic effect that was a decrease of left ventricular developed pressure and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NSCL and SCL had no effects on parameters of action potential such as resting membrane potential, action potential amplitude, APD$_{90}$ and V$_{max}$ at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NSCL and SCL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between cardiovascular effects of two preparations.s.

• 대한방사선기술학회지:방사선기술과학
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• 제47권2호
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• pp.125-135
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• 2024

This study analysed the factors that predict and influence heart disease through key indicators related to changes in left atrial and left ventricular size. Measurements recommended by the American Society of Echocardiography were used, and the influence of variables was assessed using multiple regression analysis. The results showed that left atrial volume index(LAVI) was significantly different by age, obesity, diabetes, hypertension, dyslipidaemia, and left ventricular relaxation dysfunction(p<0.05). Left ventricular mass index(LVMI) was significantly different according to age, body mass index, hypertension, diabetes, dyslipidaemia, and left ventricular relaxation dysfunction(p<0.05). Increases in LVMI and relative ventricular wall thickness(RWT) were associated with changes in LAVI(p<0.05). Age, systolic blood pressure, increased LAVI, and RWT influenced changes in LVMI, and left ventricular dysfunction was analysed as an influencing factor for both changes in LAVI and LVMI. Therefore, changes in left atrial and left ventricular size are indicators for early diagnosis and prevention of heart disease, and it is necessary to carefully observe structural changes in the heart and actively manage risk factors for the prevention and management of heart disease.

• 대한기계학회논문집A
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• 제27권1호
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• pp.167-174
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• 2003

Fatigue damage of 2.2Ni-1Cr-0.5Mo steel used fir high strength pressure tubes and vessels was evaluated using uniaxial specimens subjected to strain-controlled fatigue loading. Based on the fatigue test results from different strain ratios of -2. -i 0, 0.5, 0.75, the fatigue damage of the steel was represented by using a cyclic strain energy density. Mean stress relaxation depended on the magnitude of the applied strain amplitude. The high pressure vessel steel exhibited the cyclic softening behavior. Total strain energy density consisting of the plastic strain energy density and the elastic tensile strain energy density described fairly well the fatigue life of the steel, taking the mean stress effects into account. Compared to other fatigue damage parameters, fatigue life prediction by the cyclic strain energy density showed a good correlation with the experimental fatigue lift within a factor of 3.

• 동력기계공학회지
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• 제18권1호
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• pp.63-68
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• 2014

The numerical analysis of fluid flow in the tube cleaning system is examined. The working flow used in this study is seawater, and the temperature change is not considered as the temperature change of seawater in the tube cleaning system is negligible. Also, the analysis is performed under the assumption of steady state. The screens of complicated morphologies are simplified for the analysis, and only one fourth of the tube cleaning system is modeled as the system has a symmetrical shape. The velocity inlet boundary condition is employed for the seawater inlet, whereas the outflow boundary condition is employed for two seawater outlets. In applying the outflow boundary condition for the system with more than two outlets, the flow rate can be arbitrarily assigned. In the analysis, the finite-volume method based numerical analysis tool, the pressure based solver, the standard k-$\varepsilon$ model are utilized, and the under relaxation factor is modified appropriately. From the analysis, the distribution of velocity vectors, pressure and path lines are obtained, and the physical characteristics of fluid flow in the tube cleaning system is well-examined.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.918-925
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• 1996

The effect of structured water by dissolution of xenon was examined from the view point of the suppression of both browning and respiratory metabolism of broccoli. The structured water is formed duet to hydrophobic interaction when xenon gas dissolves into water. NMR measurements were carried out to determine proton spin-spin relaxation time, T2, for water. There was a difference in proton T2 between distilled water and structured water. This can be interpreted as the change of water structure. Fro the broccoli cut in half stored for 16 days at 279K, the section color did not change appreciably for the sample whose water was structured by dissolution of xenon whose initial partial pressure was 0.39MPa. In contrast to this, the browning of section surface was observed for the sample stored under the condition of nitrogen gas at the same partial pressure as xenon and for the sample stored under atmospheric condition . These results led to the conclusion that the suppression of b owning by oxidation was due to structured water but not to applied pressure. Adding to this, the water structured by xenon has resulted in suppression of respiratory metabolism of broccoli.