• Journal of Oral Medicine and Pain
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• v.20 no.1
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• pp.117-126
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• 1995

In order to evaluate objectively the level of tension and relaxation in dental practices, the author used Biotrainer(BF-102R), one of the GSR biofeedback apparatus, to examine 119 dental outpatients on their changes of GSR due to infection, preparation, extraction and readjustment. The obtained results were as follows : 1. There were no differences in the baseline GSR between the control group and the patient groups. 2. Changes in GSR by practices were significantly larger than the baseline GSR. 3. GSR in female was larger than that in male 4. While the GSR after injection, preparation and extraction revealed lower level, the GSR after readjustment revealed higher level. 5. Most of subjects just after injection, preparation and extraction were more frequent in decrease of GSR and those just after readjustment more were frequent n increase of GSR. 6. Type 1,2(increase in skin resistance) showed greater in injection, preparation and extraction group, while type 3(decrease in skin resistance) did in readjustment group.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1709-1711
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• 2001

The remaining life of ACSR(Aluminum Conductor Steel Reinforced) wires exposed to the atmosphere for a long period relies on the extent of deterioration caused by environmental factors such as atmospheric corrosion, galvanic corrosion, crevice corrosion and fatigue corrosion. We investigated the tensile characteristics of ACSR wires in a coastal area through several mechanical tests, and analyzed the constituents of them using SEM(scanning electron microscope). Test samples are parts of ACSR 97[$mm^2$] overhead transmission lines in that area. The result shows that ACSR wires exposed to salt may lead to rapid mechanical deterioration.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.339-341
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• 2002

The remaining life of ACSR exposed to the atmosphere for a long period may rely on deterioration caused by environmental indices such as atmospheric corrosion, galvanic corrosion, crevice corrosion and fatigue corrosion. One of reduction of useful life in overhead transmission lines built on the ridge of mountain is often caused by forest fires. This paper deals with investigation of strength deterioration performance of ACSR due to fires through several testing and analyzing data for both tension load and material analysis. Test samples are ACSR $480[mm^2]$ conductors, which are artificially fired to regular durations. As a result, it can be verified that tension load of ACSR are reduced by increasing fro duration. Hence, it is obvious that ACSR due to forest fires may lead to mechanical deterioration.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.95-96
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• 2006

ALDC 12 Al alloy is often corroded with some forms such as pitting corrosion, intergranular corrosion, and galvanic corrosion etc., in case of severe corrosion environment like seawater Annealing heat treatment was performed to improve the corrosion resistance of ALDC 12. Hardness was decreased with increasing of annealing temperature, however its corrosion resistance was clearly improved with increasing of annealing temperature.

• Journal of the Korean Ceramic Society
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• v.23 no.1
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• pp.13-20
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• 1986

Zirconia soild electrolytes containing 4~10mol% of yttria were prepared by wet-blending of oxides and rea-ction-sintering, Sinterbility and degree of stabilization were optimized for the development of oxygen sensor. Fracture strength thermal expansion coefficient electrical conductivity and galvanic potential were measured and discussed with respect to the amount of ytria addition phase transformation microstructure and degree of stabilization. It was found that sintering and stabilization occurred when the composition was designed to be near the boundary region of $ZrO_2-Y_2O_3$ binary system. In such away a good zirconia solid electrolyte suitable for oxygen sensor could be developed.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.876-878
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• 2008

The galvanic corrosion of a vessel, or systems fitted to minimize the ship's corrosion such as ICCP(Impressed Current Cathodic Protection) system and sacrificial anodes, can lead to significant electrical current flow in the sea. The presence of vessel's current sources associated with corrosion will give rise to detectable electric field surrounding the vessel and can put it at risk from mine threats. For this reason, it is necessary to design corrosion protection systems so that they don't only prevent a hull corrosion but also minimize the electric field signature. In this paper, we describe theoretical backgrounds of underwater electric field signature due to corrosion and corrosion protection system on naval vessels and analysis results of the electric field according to ICCP anode arrangement.

• Korean Journal of Materials Research
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• v.5 no.7
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• pp.842-849
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• 1995

The effect of cathodic protection by the sacrificial anode attached to condenser waterbox of power plant was investigated using numerical analysis. The condenser is consisted of various materials. So in case of no protection, the serious galvanic corrosion between waterbox and tubesheet was observed. If sacrificial anodes were attached to the wall of waterbox or the area corroded galvanically, the large protection effect was showed. To demonstrate the validity of numerical analysis results, model test was executed. The numerical solution was consistent with the experimental vague well.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.878-879
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• 2016

본 논문에서는 기존의 고비용-고정형 거짓말탐지기의 단점을 극복하기 위하여 거짓말 시 발생되는 인체의 생리적 변화를 측정하기 위한 GSR (Galvanic Skin Response) 센서와 스트레스수치 알고리즘을 활용하여 스마트폰 기반 어플리케이션을 개발 및 그 활용방안을 제안한다. 사용자에게 부착하여 사용자의 생체 피부를 통해 외적자극 또는 심적 흥분/동요 상태에 의한 활동전위 발생 정도를 측정하고 이를 스트레스 지수로 변환할 수 있는 방법을 제시한다. 또한, 사용성 및 저비용성을 보장하기 위하여, 제안하는 거짓말 탐기기능을 스마트폰 어플리케이션화 하였다.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1382-1390
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• 2017

This paper presents a power supply for gate drivers, which uses a magnetic resonance wireless power transfer system. Unlike other methods where multiple antennas are used to supply power for the gate drivers, the proposed method uses a single antenna in an insulated receiver to make multiple mutually isolated power supplies. The power transmitted via single antenna is distributed to multiple power supplies for gate drivers through resonant capacitors connected in parallel that also block DC bias. This approach has many advantages over other methods, where each gate driver needs to be supplied with power using multiple receiver antennas. The proposed method will therefore lead to a reduction in production costs and circuit area. Because the proposed circuit uses a high resonance frequency of 6.78 MHz, it is possible to implement a transmitter and a receiver using a small-sized spiral printed-circuit-board-type antenna. This paper used a single phase-leg circuit configuration to experimentally verify the performance characteristics of the proposed method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.202-203
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• 2018

Chemistry and microstructure of steel reinforcement bars play an important role to control the corrosion in concrete environments. In present study, we have chosen two different microstructure of steel rebars produced from companies and assessed their corrosion characteristics in simulated concrete pore (SCP) solution with prolonged exposure periods. Hot rolled steel rebar showed more corrosion resistance compare to thermo-mechanically treated (TMT) one. The growth of passive is greater in hot rolled (A) than TMT (B) due to orientation of microstructure. TMT steel rebar exhibit distorted microstructure with many micro cells which enhances the galvanic coupling and induce the deterioration while on the other hand hot rolled rebars exhibit fine grain boundary which responsible in growth of uniform, adherent and protective passive film resultant improved impedance was observed.