• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.180-183
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• 2008

This paper is about the ocean current power generation using sea water incoming into the lake surrounded by barrages and sea water discharged from a dam made of artificial structures. In operation of a tidal power plant, the sea water discharged from a turbine structure and a gate structure of a tidal power plant is faster than the tidal current caused by tides in nature and has better characteristics than that to run ocean current turbines. It is shown that the sea water discharged after generating electricity through a turbine generator of a tidal power plant and the sea water discharged from a gate structure of a tidal dam still have kinetic energy high enough to run an ocean current turbine and produce valuable electricity.

• Progress in Superconductivity
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• v.1 no.1
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• pp.14-19
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• 1999

Measurements across single grain boundaries in YBCO thin films and bulk bicrystals have been used to demonstrate the influence of grain boundary structure on the critical current carried across the grain boundary. In particular, we show that one role of grain boundary structure is to change the degree of pinning along the boundary, thereby influencing the critical current. This effect can be used to explain the large difference in critical current density across grain boundaries in thin films compared to that for bulk bicrystal. These differences illustrate the distinction between the intrinsic mechanism of coupling across the grain boundary that determines the maximum possible critical current across a boundary and the measured critical current which is limited by dissipation due to the motion of vortices.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.610-613
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• 2009

Uldolmok tidal current power plant was constructed on May 2009 at Jindo Gun in Korea. However it had much trouble in installing structure due to the extremely fast tidal current velocity(max. 5.5m/sec) and the jacket type plant structure. Therefore in this paper, The characteristics of tidal current and sea bed topography at Uldolmok tidal current plant site are investigated, and the detailed foundation work process of the plant is described.

• Transactions on Electrical and Electronic Materials
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• v.18 no.4
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• pp.225-228
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• 2017

In this study, zinc tin oxide (ZTO) films were prepared on indium tin oxide (ITO) glasses and annealed at different temperatures under vacuum to investigate the correlation between the Ohmic/Schottky contacts, electrical properties, and bonding structures with respect to the annealing temperatures. The ZTO film annealed at $150^{\circ}C$ exhibited an amorphous structure because of the electron-hole recombination effect, and the current of the ZTO film annealed at $150^{\circ}C$ was less than that of the other films because of the potential barrier effect at the Schottky contact. The drift current as charge carriers was similar to the leakage current in a transparent thin-film device, but the diffusion current related to the Schottky barrier leads to the decrease in the leakage current. The direction of the diffusion current was opposite to that of the drift current resulting in a two-fold enhancement of the cut-off effect of leakage drift current due to the diffusion current, and improved performance of the device with the Schottky barrier. Hence, the thin film with an amorphous structure easily becomes a Schottky contact.

• Journal of IKEEE
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• v.25 no.3
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• pp.506-510
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• 2021

In this paper, we propose an LDO that improves the load regulation change due to the current detection structure. The proposed LDO regulator adds the proposed current detection circuit to the output stage. Thereby to improve the load regulation of the delta value coming in on the output has a voltage value of an improved load Regulation characteristics than conventional LDO regulator. Using the proposed current detection structure, it was possible to improve the output change according to the change of the load current by about 60%. The proposed circuit has been simulated and verified characteristics by using a Spectre, Virtuoso simulation of Cadence.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.3
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• pp.99-104
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• 2002

lateral insulated gate bipolar transistors(LIGBTs) are extensively used in high voltage power IC application due to their low forward voltage drops. One of the main disadvantages of the LIGBT is its scow switching speed when compared to the LDMOSFET. And the LIGBT with reverse channel structure is lower current capability than the conventional LIGBT at the forward conduction mode. In this paper, the LIGBT which included p+ ring and p-channel gate is presented at the reverie channel structure. The presented LIGBT structure is proposed to suppress the latch up, efficiently and to improve the turn off time. It is shown to improve the current capability too. It is verified 2-D simulator, MEDICI. It is shown that the latch up current of new LIGBT is 10 times than that of the conventional LIGBT Additionally, it is shown that the turn off characteristics of the proposed LIGBT is i times than that of the conventional LIGBT. It is net presented the tail current of turn off characteristics at the proposed structure. And the presented LIGBT is not n+ buffer layer because it includes p channel gate and p+ ring.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.343-346
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• 1998

In this paper a radiation problem for a finite microstrip antenna structure is analyzed. For the analysis of finite structures we utilize the equivalent volume current. Intergral equation for the unknown equivalent volume current induced on a finite microstrip structure is derived and solved by the use of conjugate gradient-fast fourier. transform (CG-FFT) method. Some numerical examples are radiation patterns derived by the equivalent volume current solved by the conjugate gradient-fast fourier transform.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.615-618
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• 2003

To investigate the electrical fire identification due to conductor structure analysis of an electrical wire, we are studied by temperature heating test, over current test, short test and electric molten marks. And metal structure analysis of wire by short, we are found out increase in crystal grain with heating temperature. Structure of specimen at over current 300[%] occurred hardly structure formation and boundary of grain.

• The Transactions of the Korean Institute of Power Electronics
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• v.2 no.3
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• pp.51-57
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• 1997

A new current controlled PWM technique with N.P.C structure is proposed in this paper. A current controlled PWM technique with neutral-point-clamped pulsewidth modulation inverter composed of main switching devices which operates as switches for PWM and auxiliary switching devices to clamp the output terminal potential to the neutral point potential is described. This inverter output contains less harmonic content as compared with that of a conventional current controlled PWM type. In addition, the proposed current controlled PWM technique has lower switching frequency than that of conventional current controlled PWM technique at the same current limit. Two inverters are compared analytically. The improved voltage waveform of current controlled PWM with N.P.C structure is analyzed and the performance is investigated by the computer simulation.

• Journal of the Korean institute of surface engineering
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• v.17 no.4
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• pp.106-119
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• 1984

Brass was electrodeposited over the range of the current densities from 2 to 8 A/$dm^2$ in cyanide bath at 20 and 40$^{\circ}C$. The cathode overpotential increased and the cathode efficiency was decreased respectively with decreasing temperature, increasing current density and addition of organic substance. The perferred orientation of the deposits were associated with the cathode overpotential and the nucleation energy of lattice planes. The (111) preferred orientation developed at the low current density and low cathode overpotential (440-520mV). On the other hand, the (111)+(100) preferred orientation developed at higher cathode overpotential (528-680mV). The (111)+(100) preferred orientation developed over the whole range of overpotential in the cyanide solution with organic additive. The copper content of deposit decreased with increasing current density and decreasing temperature. The morphology of the deposits with no additive was the polygonal body type of structure and the structure of the cross section was columnar structure. The morphology of the deposits with additive, on the other hand, was fine crystallite type of structure. And the structure of the cross section of them was the finer granular structure.