• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.36-36
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• 1998

We reported previously that HERG current, molecular equivalent of I$_{kr}$, expressed in Xenopus oocytes is blocked by external $Ca^{2＋}$ and $Mg^{2＋}$. In the present study, we have investigated the effect of external H＋ on HERG current (I$_{HERG}$) using the two microelectrode voltage clamp.(omitted)ted)

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.183-189
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• 1997

This paper presents the motion of dynamically loaded journal in the connecting rod bearing of reciprocating internal combustion engine. Journal motions in engine bearings have been composed of two components, which was rotational and translational motion. Early study of journal locus in engine bearing had been performed on each motion. This paper has been considered two motions simultaneously. Reynolds equation including the squeeze effect has been analyzed using the ADI method, and real engine bearing and crankshaft system has been considered to calculate the cyclic external force. The equations of journal motion have been derived and then the numerical integration of these equations performed by 4th order Runge-Kutta method. This paper gives various journal orbits in connecting rod bearing depending on cyclic external forces, rotating speeds, and bearing parameters.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1578-1583
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• 2003

LAVA-ERVC experiments have been performed to investigate the effect of insulation design features on the coolability in case of the external reactor vessel cooling (ERVC). All the 4 tests have been performed using Alumina iron thermite melt as a corium simulant. Due to the limited steam venting through the insulation, steam binding occurred inside the annulus in the KSNP case simulation. On the contrary, in the tests which were performed for simulating the APR1400 insulation design, sufficient water ingression and steam venting through the insulation lead to effective cool down of the vessel characterized by nucleate boiling. It could be found from the experimental results that modification of the insulation design allowing sufficient ventilation could increase the positive effects of the external reactor vessel cooling.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.97-100
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• 2005

Precise prediction of resonance frequency has been the subject of numerous papers related to Helmholtz resonator design because of its high performance at the frequency. The resonance frequency is dependent upon not only the internal dimensions of resonator but also the external boundary conditions such as the existence of other resonators in Helmholtz resonator array panel. However, the latter effect, which changes the external end correction of resonator, has not been well studied. We propose a formula to calculate the radiation impedance (or external end correction) of Helmhoitz resonator array panel. Any distance between adjacent resonators and any angle of Incidence can be allowed in the method. Numerical examples show how and how much the distance affects the resonance frequency of the panel. It is also found that the maximum absorption of the panel varies with the resonator arrangement.

• Membrane and Water Treatment
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• v.1 no.2
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• pp.159-169
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• 2010

The effect of external recycle on the performance of dialysis in countercurrent-flow rectangular membrane modules was investigated both theoretically and experimentally. Theoretical analysis of mass transfer in parallel-flow device with and without recycle is analogous to heat transfer in parallel-flow heat exchangers. Experiments were carried out with the use of a microporous membrane to dialyze urea aqueous solution by pure water. In contrast to a device with recycle, improvement in mass transfer is achievable if parallel-flow dialysis is operated in a device of same size with recycle which provides the increase of fluid velocity, resulting in reduction of mass-transfer resistance, especially for rather low feed volume rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.4
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• pp.17-23
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• 1998

This paper presents the motion of dynamically loaded journal in the connecting rod bearing of reciprocation internal combustion engine. Journal motions in engine bearings have been composed of two components, which was rotational and translational motion. Early study of journal locus in engine bearing had been performed on each motion. This paper has been considered two motions simultaneously. Reynolds equation including the squeeze effect has been analyzed using the ADI method, and real engine bearing and crankshaft system has been considered to calculate the cyclic external force. The equations are performed by 4th order Runge-Kutta method. This paper gives various journal orbits in connecting rod bearing depending on cyclic external forces, rotation speeds, and bearing parameters.

• Journal of the Korean Society for Railway
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• v.9 no.2 s.31
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• pp.19-24
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• 2006

Green gas emissions Trading System(ETS) came into effect in the Europe last year 2005. All transport modes have tried to reduce green gas emission and EU member countries are promoting the use of environmental friendly transport mode to avoid economic loss due to green gas emission. Besides ETS, rapidly rising of oil price and peak oil urge to invest more in the environmental friendly public transport mode and to discourage the use of private cars. The operation of KTX is estimated to bring external cost reduction up to 570 bil. won in 2004 based on European external unit costs of transport modes. This result implies that the expansion of high speed rail network and reconsideration of East-West high speed rail network which is not considered because of weak economic validity is required.

• Journal of the Optical Society of Korea
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• v.10 no.2
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• pp.86-90
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• 2006

The external feedback effect on the relative intensity noise (RIN) characteristics of blue InAlGaN laser diode has been analyzed taking into account the spontaneous emission noise and the injection current for the high frequency modulation. A Langevin diffusion model was exploited to characterize its relative intensity noise. The simulation parameters were quantitatively evaluated from the optical gain properties of the InAlGaN multiple quantum well active regions by using the multiband Hamiltonian for the strained wurtzite crystals. The extracted parameters were then applied to the rate equations taking into account the external feedback and the high frequency modulation current. The RIN characteristics were investigated to optimize the low frequency laser diode noise characteristics.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.5
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• pp.17-24
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• 2001

Recently, the requirements for high precision and efficiency machining are gradually increased to raise international competitiveness at the industrial fields of die and molds. This trend had made effects on the industrial fields in Korea and which needs fur studying of high precision and efficiency machining. This study is to investigate the effects of the non-out of end mill in the external cylindrical machining operated by solid carbide end mills with Al-alloy in high speed machining center relating to high spindle revolution and frost fred per minute on the dimensional precision, roundness of workpiece. From the results of experimentations followings are obtained; when Al-alloy is processed by the external cylindrical cutting of end milling through the high speed revolution, if the spindle revolution is higher relating to radial depth of cut, feed per tooth in very lower situation, finally, productivity can be raised because high precision and quality products are machined high efficiently.

• International Commerce and Information Review
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• v.16 no.2
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• pp.69-88
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• 2014

This study examines the effect of external environments such as technological change and competitive intensity on standardization. It was empirically tested by a Korean sample to verify the validity of the research framework. The empirical result confirms that external environments increase the odds of marketing standardization and technology standardization. The result also indicates that technology change and global standardization are related. The data support that firms facing a high rate of technology change stress marketing and technology standardization. The result also confirms that competitive intensity directly influences marketing standardization.