• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.8
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• pp.807-812
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• 2015

Li-ion batteries are energy sources that are widely used in applications such as notebooks, cellular phones, power tools, and vehicles. They are devices in which stored chemical energy is changed to electrical energy by electrochemical reactions. They have a high energy density, small size, and are lightweight. In particular, power tools and vehicles require high charge/discharge rates. Therefore, in this paper, we perform electrochemical simulations using a commercial finite-element analysis program to determine the high discharge-rate characteristics of Li-ion cells. In addition, by performing high discharge-rate simulations, we found that the limited discharge current was 63 A. Based on the results obtained, we investigate the behavior of Li-ion cells with a high rate of discharge.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.2
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• pp.103-111
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• 2013

In this study, field measurements were conducted in the section about 7 km from sea dike to westward. The observations of along channel current were carried out, and water temperature and salinity were measured simultaneously at 10 stations during one tidal cycle, and sampling interval is 1 hour. The maximum ebb current is about 1.5 m/s at the surface layer but flood current is 0.4 m/s at the bottom layer during discharge period. Residual current during river discharge shows two layer structures which is typical characteristic of the estuary system. On the other hand, residual current during a period with no discharge has shown multi-layer structure different from general estuarine systems. The distribution of high salinity can be seen at the bottom layer as the effect of discharge does not reach down to the bottom layer during discharge. As a result, freshwater is not effected at the bottom layer during observation, and mixing of surface layer to bottom layer is reduced by stratification.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.8
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• pp.611-620
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• 2020

The effect of discharge voltage on electron mean energy, electric potential, ionization rate, neutral and ion density of Hall thruster was analyzed using a two-dimensional axisymmetric hybrid model. The results of the code developed for this study such as discharge current, thrust, and plasma distribution according to discharge voltage of SPT-100ML Hall thruster were compared by experiments and calculations of other researchers for validation. The results show that the electron mean energy, the ionization rate, and the ion density are increased while the neutral density is decreased as the discharge voltage is increased. The thrust and the discharge current are proportional to the discharge voltage.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.3
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• pp.51-56
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• 2001

In this paper, the effect of magnetic field on corona discharge phenomena was experimentally investigated in the needle-plate electrode geometry. Needle-plate geometry discharge system with magnetic field at a right angle to the electric field was made. The corona discharge characteristics with magnetic field were investigated and compared with the corona characteristics without magnetic field in atmospheric pressure. As a result, in case of positive DC corona discharge with magnetic field, corona discharge zone was significantly wider, corona current was lower, and breakdown voltage was higher than those without magnetic field. However, in case of negative DC corona discharge with magnetic field, corona current was slightly higher and breakdown voltage was lower than those without magnetic field. It is thought that this result is due to cyclotron motion of charged particles such as electron and ion by magnetic field.

• Journal of Ocean Engineering and Technology
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• v.18 no.5
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• pp.22-28
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• 2004

This study constructed a 3D real-time numerical model that predicts the water quality and movement characteristics of the inner bay, considering the characteristics of the wind-driven current and density current in estuaries, generated by the river discharge from the Hyeong-san river and oceanic water of the Eastern sea. The numerical model successfully calculated the seawater circulation current of Yeong-il Bay, using the input conditions oj the real-time tidal current, river discharge, and weather conditions during March 2001. This study also observed the wind-driven current and density current in estuaries that are effected by the seawater circulation pattern of the inner bay. We investigated and analyzed each impact factor, and its relationship to the water quality of Yeong-il bay.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.527-530
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• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generate from gas discharge and powder type electrolyminescent display(P-ELD) using a phenomenon of the light emission eaused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1792-1794
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• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generated from gas discharge and powder type electro luminescent display using a phenomenon of the light emission caused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.10
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• pp.384-388
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• 1985

In this paper, an attempt is made to derive the variation equatios of the discharge current and the luminous flux for flourescent lamp subjected to a transverse magnetic field. As the field increases, so do the electric field, the electron temperature, and the luminous flux, while the current decreases. The theory is in a reasonable agreement with the experimental results, taking account of many approximations and restrictions.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.316-318
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• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generated from gas discharge and powder type electrolyminescent display(P-ELD) using a phenomenon of the light emission eaused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.305-307
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• 2001

In this paper, the basic characteristics of flat fluorescent lamp using ultraviolet generated from gas discharge and powder type electro luminescent display using a phenomenon of the light emission caused by the electrical field applied to phosphor are studied. The lamp is a simple structure with insulator layer, phosphor layer, and gas gap. Current(displacement current + discharge current) in flat fluorescent lamp using.