• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1065-1068
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• 2003

The nano imprint process is one of the next generation lithography has been mentioned as one of major nanoreplication techniques because it is simple process, low cost, high replication fidelity and relatively high throughput. This process requires a surface contact between a template with patterns and a wafer on a stage. After contact, the vertical moving the template to the wafer causes some directional motions of the stage. Thus the stage must move according to the motions of the template to avoid the damage of the transferred patterns on the wafer. This study is to develop the wafer stage with a passive compliance to overcome the damage. This stage is designed with the concept like that it has a monolithic, symmetry and planar 6-DOF mechanism.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.137-140
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• 1996

This study investigated the length-tension and velocity-force relations of the torso erectors. A myoelectric based approach was used wherein a dynamic biomechanical model incorporating active and passive tissue charactreistics provided music kinematic estimates during controlled sagittal plan extension motions. A double linear optimization formulation from the literatured provided muscle tension estimates. The data supported a linear length-tension relation toward full flexion for both the erector spinae and latissimus muscles. Velocity trends agreed with that predicted by Hill's exponential relation. The results have implications for muscle tension estimation in biomechanical torso modeling, and suggest a possible low back pain injury mechanism.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.283-284
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• 2006

The ship performs heat exchange using seawater to keep main engine and auxiliary machinery at optimum temperature. In heat exchanger, refrigerant located outside of copper tube is cooled by seawater flowing through inside of copper tube. On the other hand, seawater erosion and corrosion nay occasionally cause the corrosion of the copper tube in A/C(Air Conditioner) condenser. This corrosion of copper tube makes seawater and refrigerant mixed, seriously damaging A/C system. In this study, accordingly, the exact ive mechanism of the corrosion on the condenser entailing serious problems occasional is investigated through the electrochemical polarization experiments on the condenser's component materials. According to the experiments, the corrosive procedures on the copper tube was verified by the fact that passive film of the copper tube surface which is destroyed by the pressure of sucked seawater, is damaged by the corrosive ingredients in the seawater.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.420-425
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• 2001

Theoretical analysis of noise reduction by a membrane-duct system is presented. When acorn waves propagate in the membrane-duct, the membrane is also excited and its motion is coup with interior medium. It has been shown that propagating waves with supersonic wave speed exist beyond a certain critical frequency that is determined from the mass ratio of the me and the fluid. Also found are subsonic waves which couple strongly wi th the membrane a provide a powerful mechanism of energy dissipation. Existence of an exterior medium alter dispersion characteristics. It provides additional mass loading and reduces the subsort speed further. The effect of mean flow speed on dispersion characteristics is also consider results show that the membrane-duct system can be applied to diminish and absorb 1 frequency noise in duct instead of passive muffler, such as a simple expansion chamber absorption material.

• 아시안잔디학회지
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• 제11권1호
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• pp.9-22
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• 1997

This study was performed to elucidate the mechanisms involved in efflux process of phosphate from intact and excised roots of Oryza sativa (Tongil). The rapid loss of phosphate during the first 40-minutes of treatment is mainly from the cytoplasmic fraction, and the gradual loss taking place afterwards is possibly reflecting the losses at the tonoplast. During the first 60 minutes, loss of phosphate from the excised roots treated with KCN was more rapid than the control but slower thereafter. The effect of $CaCl_2$ and KCl appeared to decrease the rate of phosphate efflux in excised roots of rice. The mechanism of phosphate efflux by rice roots seems to be passive and oscillatory in the short period. Key words: Oryza sativa(Tongil), Phosphate efflux.

• 약학회지
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• 제49권5호
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• pp.386-391
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• 2005

The discovery of drugs for the treatment of mast cell-mediated allergic disease is a very important subject in human health. The Amomum xanthiodes (Zingiberaceae) has been used for centuries as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. In this report, we investigated the effect of hot water extract from Amomum xanthiodes (EAX) on the mast cell-mediated allergic reaction and studied its possible mechanisms of action. EAX inhibited compound 48/80-induced systemic anaphylaxis and serum his­tamine release in mice. EAX decreased the passive cutaneous anaphylaxis reaction activated by anti-dinitrophenyl (DNP) IgE antibody. EAX dose-dependently reduced histamine release from rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE. EAX increased cAMP and decreased compound 48/80-induced intracellular $Ca^{2+}$ levels. Our findings provide evidence that EAX inhibits mast cell-derived allergic reactions, and also demonstrate the involvement of cAMP and intracellular $Ca^{2+}$ in these effects.

• 천문학회보
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• 제43권1호
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• pp.62.3-63
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• 2018

Trends of Type Ia supernova (SN Ia) luminosities with the properties of host galaxies are important to study the underlying physics for an SN progenitor system and explosion mechanism. In the YONSEI SN catalog, we have a sample of ~600 SN and host data in the wider redshift range, and two independent light-curve models, SALT2 and MLCS2k2. From this catalog, here we present that SNe Ia in low-mass, globally and locally star-forming environments are fainter than those in high-mass, globally and locally passive environments, after light-curve shape and color or extinction corrections. Our results are then compared to previous studies, and show consistent results.

• Journal of Mechanical Science and Technology
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• 제18권1호
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• pp.173-182
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• 2004

The present study has focused on numerical investigation on the flame structure, flame lift-off and stabilization in the partially premixed turbulent lifted jet flames. Since the lifted jet flames have the partially premixed nature in the flow region between nozzle exit and flame base, level set approach is applied to simulate the partially premixed turbulent lifted jet flames for various fuel jet velocities and co-flow velocities. The flame stabilization mechanism and the flame structure near flame base are presented in detail. The predicted lift-off heights are compared with the measured ones.

• 소음진동
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• 제7권5호
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• pp.765-772
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• 1997

This paper presents the swing motion analysis of the container crane headblock with the passive control device using hydraulic motors and anti-swing ropes. The device hauls at the headblock to opposite direction of its swing motion using the tension difference between anti-swing ropes connected to the headblock. To consider this control mechanism, the headblock is modelled as the rigid bar suspended by two hoist ropes at the overhead trolley and its non-linear equation of motion is derived using Lagrange's equation. Some numerical experiments using the equation are carried out to investigate the swing motion characteristics of the headblock under the variation of geometric relation among the cargo handling components and to evaluate the performance of the anti-swing device.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.153-159
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• 1997

This paper presents the swing motion analysis of the container crane headblock with the passive control device using hydraulic motors and anti-swing ropes. The device hauls at the headblock to opposite direction of its swing motion using the tension difference between anti-swing ropes connected to the headblock. To consider this control mechanism, the headblock is modelled as the rigid bar suspended by two hoist ropes at the overhead trolley and its non-linear equation of motion is derived using Lagrange's equation. Some numerical experiments using the equation are carried out to investigate the swing motion characteristics of the headblock under the variation of geometric relation among the cargo handling components and to evaluate the performance of the anti-swing device.