• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3513-3516
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• 2011

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1682-1684
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• 2001

In removing the flue-gas using electrical discharge method, it is important to dissociate or ionize the atoms and molecules by the collisions with energetic electrons and it produces the radicals that are used to decompose the pollutants. For that purpose, a bidirectional pulsed voltage is used to produce lots of energetic electrons efficiently and increase the power efficiency. The simulation is performed with changing the pulsewidth under the fixed applied voltage. The particle-mesh model coupling the NGP(nearest-grid-point) to FEM(finite element method) is used to simulate the behavior of electrons and the spatio-temporal variation of the electric field for the streamer in discharge tube.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1913-1917
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• 2000

SMD Equipment convey an electronic parts at high speed, then assemble parts into a circuit board, and it develop a long time-duration dynamic force to be caused by moving mass. Vibration problem to be caused by SMD Equipment have an effect on micro-meter level's precision production process, directly, and dynamic stability of building. In the cause of quantitatively access about its vibration problem, input information(or data) of structure dynamic analysis need accuracy information of dynamic load. Determination of Dynamic load is various kinds of method using experimental and theory. In this paper, we got dynamic load using direct measurement method. We expect that an study on the dynamic load characteristic of SMD can be used to Equipment development of low level vibration and basis information of structure dynamic analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1945-1950
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• 2000

When one build a building that posses Precison production process to be sensitive to vibration and SMD to procuce a large dynamic force, how do one predict & answer vibration control problem at building structure design at first stage, That is a question. It has tried to predict dynamic response and establish answering about global or local dynamic problem in building using experimental and analysis method. One of such a try, it be proposed Semi-Empirial Method that reduce error element of input information about dynamic analysis using dynamic experimental study and measurement data in the basis of real-structure. In this paper, the dynamic response problem about RC-structure building that will be set-up SMD produce large transient dynamic force using Semi-Empirical Method.

• Journal of the korean society of oceanography
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• v.33 no.1-2
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• pp.1-7
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• 1998

In the western Weddell Sea, winter mixed layer is characterized by near-freezing temperature and higher salinity due to brine injection through sea-ice formation. This layer becomes Winter Water being capped by warmer and less saline Antarctic Surface Water during the sea-ice melt-ing season. In this study, Winter Water was preliminarily identified by the oxygen isotopic com-positions. The ${\delta}^{18}$O values of Winter Water show the progressively increasing trend from south to north in the study area. It presumably reflects the enhanced mixing with Antarctic Surface Water due to the extent of influence by low S'"0 value of sea-ice/glacier meltwater. Correlations between salinity and 6'"0 values of seawater can be used to more generally characterize Winter Water with a view to identification. However, the prediction on the degree of mixing from these relationships needs more detailed isotope data, although this study allows the oxygen isotopic composition of seawater as a tracer to identify the water mass.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.162-166
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• 2014

정밀 장비의 진동 허용치는 장비의 성능을 저하시키지 않는 외부 진동의 허용 범위를 의미하는 것으로 BBN 기준, NIST 기준 등이 있다. 반도체 및 디스플레이 산업 현장에서 주로 적용되는 BBN 기준을 평가하기 위해 측정시 측정자에 따라 상이한 결과가 발생하기도 한다. 이는 계측기의 설정 및 분석 방법 등 측정 방법의 차이에서 기인하는 것으로 관련된 측정 방법에 대한 가이드가 없기 때문인 것으로 보인다. 본 논문에서는 BBN 기준 평가를 위해 정밀 장비의 진동 허용치를 측정시 분석 방법, 평균화 방법 및 등급 판정 방법에 대한 가이드를 제안한다.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2284-2286
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• 1999

This paper describes the development of potential detection system in 22.9kV gas insulated switchgear. This system composed with main system and LPS can detect the source voltage by capacitive potential division which is accomplished by inserting signal electrode between main electrode and earthed metal enclosure of the switchgear. The appropriate position of signal electrode is achieved by numerical analysis using finite element method. The developed potential detection system is verified by several tests such as voltage test, swc test and others and by applicaion at site. From the results, it is concluded that potential detection system is very reliable and available to operate the switchgear safely.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1681-1683
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• 1997

Linear induction accelerator devised for high current beam accelerating is divided into two types. In the first type, a unidirectional pulse is injected to an accelerating gap and in the second type, a bidirectional pulse is injected. The purpose of this paper is design and manufacture of bidirectional pulse generator for linear induction accelerator, where the pulse width for acceleration is more than 50[nsee] and the designed maximum charging voltage is more than 200[kV].

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1323-1325
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• 1997

The necessity of this work is described with present problems in the application of computer simulation methods to electrical material research. Author proposes and develops method which can calculate properties such as dielectric and piezoelectric constants for ZnO. The method based on ab-initio method. It is found that these properties can be calculated with a good precision by this method.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2000.06a
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• pp.123-123
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• 2000